9 Major Cities:
Ok, here is a list of the 9 major cities in the providence of Cyrodiil (please note that Kvatch does count as one of the 9 major ones, even though it's destroyed). Special thanks to Astarsis for the list:
> Anvil - Southwest (Italian type port city, stone buildings with red tiles rooftop)
> Bravil - South (Small rundown buildings)
> Bruma - North (Skaal type city)
> Chorrol ? Northwest (26 houses, walled city, fort, church with green windows, classic imperial style, God: Stendar)
> Cheydinhal - Northeast (Wooden buildings, paradise pond and natural surroundings, God: Arkay)
> Imperial City - Central Island (Capital, 2.5x Vivec, main hub 4x Chorrol, 100 NPC?s, smaller hub and port around, roman stone builder with green rusted cooper domes, God: Talos (Tiber Septim))
> Leyawiin - Southern Jungles (rural/wooden style with brown wooden buildings, long with high farm-style roofs)
> Kvatch - Southwest (Seems classic imperial style but in ruins, God: Akatosh)
> Skingrad - Southwest (Tall stone buildings)
Additional Note: You must use the city gates to enter and exit cities with walls now. You will be unable to levitate/jump over the walls (but you will be able to see landscape if it?s high enough to be seen over the walls). It has not been stated exactly how the devs plan on implementing this limitation.

The Arena (Guild):
You?ll be able to bet on fights as well as work your way through the ranks.

The Blades (Guild):
You?ll most likely do quests for them during the Main Quest (and perhaps various side quests), but will be unable to join.

Borders:
Borders are invisible walls that prevent you from going beyond the edges of Cyrodiil. These borders will be comprised of natural boundaries (i.e. rivers, mountains, etc.) and other times will just be unnoticeable invisible barriers blocking your path with a message telling you to ?go back?.
Additional Note: You?ll still be able to see ?beyond? the borders so you don?t feel awkward about them.

The Counts (5 Houses):
You'll be able to do quests for the five Counts that are fighting for power in Cyrodiil, but will be unable to join any one of them.

Dark Brotherhood (guild):
To gain admittance, you will need to kill someone innocent. Only then will someone confront you about joining the guild.

Expanded Character Creation Process:
The new character selection has gotten a complete overhaul from the one in Morrowind. You will now use sliders to pick custom age, face, brow, cheeks, chin, forehead, jaw, mouth, nose, skin tone, beard, eyes, eyebrows, lips, and nose (eyes will be chosen from a list). There will be no ability to change body type (as this could result in clipping issues). Also, age will be a cosmetic effect only. It will have no effect on starting stats, or affect your stats while playing the game. No character will age in game.
Additional Note: There will be no modeled beards/facial hair. There will only be beard/facial hair shaders, so you will look like you have a heavy 5 o?clock shadow. Also, there is a RGB slider for hair color, so hair color can be as wild as you want.

Forced Reloads (No List):
Ok, they changed it again, and to our liking, I?m sure. They have taken out the forced reload and inserted in its place a new condition. If you happen to attack and kill an essential NPC, they don?t die, but instead go unconscious for a time. Eventually they will get back up, and go about their daily business (most probably with a lowered disposition towards you for killing them).
Additional Note: Fortunately, it has been said that when an essential NPC has served their purpose, the flag on them will be turned off and you can kill to your hearts content. Also see the Yielding footnote.

Improved Combat:
With the new combat system implemented you'll be able to manually block, attack quickly using different combos, or use one of the five 'special' or 'super' attacks (per skill) all of which have their own benefits when fighting. Holding up you shield will slow you down (unable to run), and you also have to be facing your opponent to block an attack. The block skill will govern all effectiveness of blocking, whether it is done with a weapon, shield or your hands. Blocking with a weapon or shield absorbs damage from the attack (preventing some of it from getting to you), but they will also take damage. Blocking with you hands will not absorb weapon damage, only hand to hand damage. Additional Note: Also this time a hit is a ?hit?. There is no ?to-hit roll? for hitting or missing, it only does ?rolls? on your stats and skills to determine what damage is done to the enemy. Also see the Yielding footnote.

Interactive Jail (Escaping):
Picking the lock, stealing the key from the guard when he walks by, starting a fight with the other prisoner so the guard investigates, bribe the guard (possibly), wait until another prisoner is to be released and then run out of the cell, etc.

Lockpicking Mini-game:
You are now taken to a different screen when attempting to pick a lock. You will now have to use a lockpick to tap tumblers into the ?unlock? position. The harder the lock, the more tumblers there are and they are difficult it is to lock the tumblers in place. Additional Note: You can tell the game to solve the lock itself without having you do it manually, and the game does a dice roll against the lock using your security skill. The higher your skill, the better chance it opening without breaking your pick.

New Persuasion Interface:
In the E3 demo, we saw a new interface that was almost a mini-game in itself, where you pick a choice with your cursor (Boast, Admire, Joke, Bully) and watch the NPC reaction to guage which one to choose. Since then we have been informed that that interface has been scraped and a new one is in it's place. At the moment, we have no new information about it.

Potion Application to Weapons:
You when you make a potion, you can use it on a weapon of your choice to add that effect to the weapon, and will be transferred to the next person you hit with the effected weapon. A small green droplet icon appears on the screen indicating a potion has been applied to the weapon

Radiant AI:
NPC?s will have 24/7 schedules, such as closing their shop at night, or locking their door when they go to bed. They also have full facial expressions and will react accordingly to what race they are talking to (High Elves would have a lower disposition to a Wood Elf, than say another High Elf). Additional Note: It has been said that NPC?s will have many more parameters that go into decisions that they choose. Just a couple of them are confidence and responsibility.

Realistic clothing movement
(Maybe List): Clothing is still unsure, but there will be no "bouncy breasts" or movable hair on characters. There will be tails though, and they will be "havok'd". Unfortunately the thread this issue is gone, and the topic is just about dead. If anyone finds a new one, please contact me and I'll post the link to it here.

TES Construction Set:
The CS has been improved to be simpler for the developers and modders. Dialogue, landscaping, quests, scripting and more have all been made easier to use. Modders will still need a separate program to create objects, and another for skinning (just like for Morrowind). Here is a quick rundown of some improvements to the scripting:
> Ability to call functions on any reference anywhere
> If statements can use the full range of logical operators: &&, 7C7C, >, !=, etc., as well as nested parents
> Integration of script functions with "conditions" in the editor -- basically, any function that returns a value will be available to conditionalize dialogue, etc.
> Variables can be used as parameters for most function calls
Unfortunately arrays, lists, pointer and string variables are unlikely to be added.

Thieves? Guild:
To gain admittance, you will need to be thrown in jail for a non-violent crime, or go through the conventional means of talking to NPC?s.

Vampires:
If you should become a vampire you'll still be able to continue the main quest, possibly everything, except that you'll be required to get your daily helping of blood. With that, you should be able to withstand the suns rays for the most part, and will be less recognizable as a Vampire to most people.

Yielding:
To balance the improved combat and help solve the essential NPC issue, the yield system has been implemented. So if in a fight with any NPC, there is a chance they might yield (based on their disposition, will to fight, etc.). You also have the chance to yield yourself (just by clicking on the NPC during combat) and they can either accept it or continue to fight (based on the same stats above). Additional Note: Creatures will never accept if you try to yield to them. Also see the Forced Reloads and Improved Combat footnotes.