For me, undoubtedly it's the fact that quick cast is gone, meaning if you're wielding a two-handed weapon you have to sheathe it to cast spells. Words cannot express how much this irks me.

The fact Meeko is dead on my char.

Leveled loot.

the lack of underwater combat of any kind.

My puny shout capabilities.

Lack of RPG qualities, lack of meaningful dialogue and lack of character advancement. You don't have it any easier or harder if you are level 1 or 81.

The lack of them talking about the world around Skyrim.

Any word from the other provinces?

Auto health regen.

When you ask like this, I can't find an answer. My problem is more about the lack of things. Perfection without substance.

Oh, yeah. Leveled loot, more precisely level scaling in general.

The thing I dislike the most is the amount of whiners and crybabies the game has created.

The compass

Cicero

Comes with attracting the cod crowd.

The forums, and the usual bawling that comes when a company actually wants people to buy the game and merely look like they want to attract someone that aren't the hardcoes.. (See, signature, post above, etc)

Really, the absolute nerfing of Destruction magic is probably it. I loved playing mages in Morrowind and Oblivion, but in Skyrim it's not as fun. You can't rely on Destruction as you get stronger, not without using the "-% to cast" enchants/Impact trick, or carrying a ton of potions.

I've got way too many for it to only be one thing.

No Weapon Armor Degradtion
Preset Character Creation (Oblivion's was better).
No skippable Tutorial
Less Attributes
Horrible Journal
Too many terrible quests.
Horrible Dialoge
Esbern, Esbern and more Esbern, oh and let's not forget Delphine too.
Finite Merchant money
Companions Guild
Marriage (It's shallow)
No combat in Water
Auto Health Regen
No Spell Creation
Less Skills
Bugs that make the game unplayable, plus another +100 things I could add. I love Skyrim but I'm starting to notice the flaws and that's not a good thing. I can deal with the flaws that Oblivion and Fallout 3 have but the flaws that Skyrim has are something that I can't ignore.

Lack of unnarmed skill tree.

And the Blades. Make them "unessential" during the Parthurnaax quest.

1 Mile wide, 1 foot deep.

Skyrim Why you no give me more, why you so shallow, why you stop short or rush me JUST when things get interesting. Why aren't you Epic in depth as you are in scale.

mine BY FAR is the stuff in my house diappearing into the walls..

WOODEN MASK!! it went from a displaycase in Hjerim straight into the wall so yeah, thanks, thats the end of the 9th dragon mask
Nettlebane went from a weapon plaque into the wall
Bust of the grey fox, was on the floor, away from any object.. was gone ..

unbelievable!! i would settle for far less grapics if it would mean my important stuff wouldnt just dissapear!!

and just as im typing this and my screensave in the game is going round i hear a sound and bust of the grey fox falls on the floor next to me..
nut wait, now i turn around ans bee in a jar is gone, had been sitting there for ages... but now its gone..

FFS please bethesda, this would be THE most annoying thing in the game!!

Yep. Shallow rpg mechanics, shallow writing, shallow quest design, shallow npcs, shallow combat. Everything is shallow. World is pretty, but it doesn't matter if I don't care about anyone or anything living in it. Dragons come off as dumb animals despite being supposedly intelligent.

No mounted combat

Overpowered crafting skills and a complete lack of spell diversity.

My biggest gripe? Short, shallow, uninspiring quests.

Just finished the Comanions Guild yesterday and got to thinking that it, along with much of the rest of the game had real potential to be something spectacular, but somehow everything important fell flat.

My opinion is one that I think Bethesda tried to do too much, tried adding to much to the game, and the whole damn thing suffered because of it.

Quest lines have been reduced to utter crap. That's my number 1 gripe.

the magic system is really boring and unbalanced