First off the reason this comes to mind is part because of RAI and part because on my MW I have done EVERY single quest, even the people on dirt paths and such, systematically went over the ENTIRE map, done every house (seperate game for two) and faction quest, even when I could already be head of the guild. All the guildmaster quests, have 100 in every stat and skill w/o and use of trainers or magic, no cheats, just over 5000 hours of gameplay over several characters, over 300 just on my main character and I am now systematically killing off every single inhabitant of the game, but of course the guards and animals/enemies will respawn. And my character has been in MW over 3 years (lost track honestly) of in game time (715 days with shorter game years than real life's).
That (bragging, sorry) aside here's my point

Characters in Oblivion need to eat, which is a new problem. They can even kill for it if they don't have any....SO
Is there enough food that grows per month/unit of time to account for the food consumption of over a thousand NPC's or are they going to attack me for food I carry after a couple years?
Maybe I just need to kill like three hundred and then the food will grow fast enough to meet demand.....or can they acctually plant their own to save them from being a problem?
I would be surprised if the game testers were testing the same build long enough to get a full spectrum of time on a multiple year scale before they were given the next build to start testing with improvments on the old one....I am looking forward to seeing how this will be handled.
This is more of a potential problem on the xbox 360 version because they can't go in and just add food to solve to problem themselves as it might arise (I am getting the PC version and adding a huge autonomous area that will be a plpayground for a couple people I have gametesting for me on my LARP game I am designing.)

I am assuming both creatures and plant ingrediants respawn relatively quickly, ingrediants probably no longer take a month to respawn and since it will all most likely be a big cycle they would only need to test it untill any beginning resources have be expended and for one full respawn, then the same thing would happen over again and again. Though I am wondering how they will deal with the economy, I think they've said that NPCs can both buy things and can run out of money; income could not be realistic because then all the money would end up in 1 place so I'd assume they give a person a set amount of money each month which will get them by but the player could steal/sell stuff which would lower their money and force them to hunt. Likewise if the player bought stuff off them it could go into savings, perhaps disappear or something.

All in all the city workings will be very interesting in OB but I think they would have tested it (because they would have had to) and implemented something which works.

Well, appearently NPCs can plant and grow food, so many people will be saved from starvation. The others? They probably have an NPC economy.

As we have all seen in the fifth E3 video, NPC's train their skills, in the long term, ie. over 600 days, would these NPC's start to max themselves out? and if so what would they do instead of training?

Also, I don't know about other people but I have been known to fall asleep while playing, could the NPC's end up being like...twice as powerful as the PC?

Maybe there is a cap installed that makes them read the same book over and over if they get to a certain skill level in direct realtion to your skills levels...like if you have 20 in all 21 skills they stop training when they too have 420 total skill points. Anyone know anything or care to speculate? (this post was a nicer size...)

Training will probably be an aesthetic scripted thing, they will probably only train 1 skill so if they maxed out in that training wouldn't raise it any more but they'd still probably do it. They might not actaully skill up through training, it could be purely aesthetic.

NPCs can't die of starvation. They don't have a little hunger meter. They just have general goals, and that goal is to eat at ******* at **** time. So running out of food isn't much of a problem.

It is if they want food, don't have it as a city and you walk in carrying all your high and mighty deer meat from the feild......you would get bum rushed by the whole town because they have been trying to meet that 9am eat command and it's 3 now and they are being told to eat for lucnch......RUN AWAY.... I know that they don't die, that would acctually make things easier in some senarios, but worse in most....also with skill training I don't think it would be a purely aesthetic thing because they get the same increases from potions etc. as you do, so they would not have any reason not to also get skill points, anyways I don't like mindlessly speculateing, which is about what this has boiled down to for me, what I was really hoping for was a dev to reply b/c I understood all the possibilities before I ever put the topic up, I have a mind of a game tester/exploiter so I go through all the possable solutions to problems in a matter of under 30 seconds usually, it's a really nice ability, but it can make some things boring....damn high IQ....j/k I appreciate all people of all IQ's...for different reasons....