This probably isn't as big of a deal as half of the problems other's are facing but this is my only problem(so far) and I'm wondering if anyone else is experiencing it too. Most of the places I've gone to I've cleared out and once I come back theres nothing new there. I've heard things should respawn after a few days/weeks(depending on dungeons and caves and just roaming around) but I've waited several months and nothings returned. My favorite thing was coming back to dungeons I've onced cleared and seeing newer stronger enemies in Oblivion so this kind of upsets me that this would be different in Skyrim. If anyone has anything to add or if anyone's seeing this problem in their game as well please post. Thanks. (oh and I sent a message to Bethesda a while ago and told them((not complaining just saying)) and I'm still awaiting a reply, and I realize they are probably swamped with people complaining and commenting so that's understandable)

As we currently understand it...

1. Exterior world game cells are to re-spawn after 240hrs (10 days).
To test: Avoid the area for 11 days, make a save, then travel and take a look.
2. Interior game cells (caves, forts, etc) are to re-spawn after 720hrs (30 days).
To test: Avoid the interior area for 31 days, make a save, then travel and take a look.
3. Ore deposits, be they surface or within mines, are supposed to re-spawn after 30 days.

Note: You must visit the area for it to actually reset.

It's currently somewhat working on my game (v1.3) yet inconsistent.
Some but not all ore veins re-spawn.
Most wildlife spawn points have new critters, though some of the previous carcasses remain.
NPC enemies (bandits, forsworn, etc) seem to be re-spawning correctly.

Until Beth begins rolling out data fixes in January, your best action is to save before returning to a *hopefully* re-seeded location.
Check it. Good? Save and proceed. Not good? Reload and wait longer.
Hope that helps

Thanks. For some reason though ABSOLUTELY NO people or creatures within dungeons will respawn. And a few certain areas outside will respawn some enemies(though fewer in numbers or now none at all) I just hope they eventually patch this as it is quite hard to get 100 one handed, two handed, archery, and destruction with nobody to kill . And I've tried waiting several months in game just saying. Thanks .

I've waited over a year in game time now and several outside cells have yet to respawn. I think some alchemy items are not respawning. The enemies drop their weapons and stay on the ground forever and that happens in locations where the enemies do not respawn it might be related in some way. Also I think the none disappearing ash piles are responsible for no respawns. It's worth noting too that when I go to some areas only one person has respawned and the rest are nowhere to be found.

I have some shop owners that have died and three months have passed in game, and no new owners have appeared. I thought bethesda said the game would spawn people to take over shops if the owner died.

In some shops the apprentice is supposed to take it over, but for the most part that feature did not make it in the game.

I tested it because i noticed the same at Valtheim Towers , i just slept for one month and returned no enemies there . i cleared the area in the beginning .

That is one place for me it only seems to happen in above ground cells so far.

My places that have not respawned are,

Autumshade Clearing
Fort Greymoore
Faldors Tooth
Valtheim Towers
Broken Tower Redoubt
Robbers Cove

I think that is it, I have tested all of these locations retiring months later and still nobody is there.

Maybe they did some changes too reduce lag and maybe it needs too be tweaked again

One thing to remember: You must visit a spot in order for it to re-spawn.
I'll use ore for an example.

1. You've avoided a certain mine for 30 days, then enter and find the veins all shiny and ripe for the picking. However...
2. No option is available to mine the ore. What?!!?
3. Hovering the reticule gives no *A* button option to mine but you can clearly see the vein has fresh color.
What gives?

Solution: Exit the mine and re-enter. The veins can then be mined.
You've avoided the area for the required time and, indeed, the veins have re-spawned. The option to mine again, however, is only available after you've re-visited the site. Remember; it re-spawns the veins when you re-enter. You must exit and re-enter again in order to have the option to mine.

Tested at Shor's Stone (Redbelly Mine), Darkwater Crossing (Goldenrock Mine), Embershard Mine, and Kynesgrove (Steamscorch Mine).
I purposely chose 4 different ore types, and every single one required me to enter/exit/re-enter in order to activate.
Hope that helps.

If anyone tests ore and finds anything different than what I've reported, please post so we can try and get an actual answer. I know what I've personally found and that's all I know. Even then, this is just conjecture whilst trying to figure it all out. We can only form solid info if we continue to help one another.