What I noticed:
True European art style for Nords
Cinematic style intro, VERY breathtaking
Confused as to what the hell is going on when a dragon attacked. Now that I think about it, THAT's one heck of an immersion there.
Skyrim is still comprised of indoor and outdoor cells
The UI is craptastic
Time no longer freezes as I talk with someone
The environment is many times more beautiful than Oblivion
Innocent creatures in the wilds. Bunnies! Deers! Goats! Foxes! Oh MY!
Cows. HOLY CRAP! Finally! A commodity animal!
Chickens! Dear Akatosh, this looks too good to be true!
I can't jump high enough
The map is craptastic in showing the way, especially the effing clouds

just remmebered before falling prey to a coupel of giants the snow drifting off the mountain surface around me in the wind currents was so beutiful

I noticed the beautiful world and how alive it felt. Then after that I began noticing the bugs.

The giants! Yes! It was VERY awesome. They look a bit small from the distance, but as I get near them they grow bigger, and as they walk the ground itself trembles. I love the execution of that. I can't kill 'em when I was level 3, and I said: boy, am I happy to see this kind of boss

at level 2 i half killed 1 then got golf clubbed by another that i didn't see

(didn't even see the 1st one till started trying to crush me)

I remember thinking "Don't run you fool!" When the one prisoner tries to make a run for it! LOL
And then I thought how unfair it all was, my name wasn't even on the list.

In all the confusion that ensued, I just followed the first guy I saw. Once we emerged out of the keep and I could finally inhale the cold Skyrim air as a free woman, the beauty of the land just took my breath away. I played that toon for maybe 10 levels and then decided to start over with a True Nord Woman! hahahahaha (Payback for what the Imperials did there psh). She's level 56 now, finished all the main quests and all the guild quests, but there's still stuff left to explore.

I'm also playing an Imperial and now I started a Breton. LOL

+1

this happens to me alot when playing beths game, may start telling the misses salad or sandwich only when tes is in, cold stew is rank...

i remember noticing the river current on the pc, bird nests and brillent sky, unfortunity i also noticed 'ownd beds'

great lifelike and natural opening showing great graphics, a beheading and awesome dragon mechanics
finally, a great snow-filled land with harsh environment and wildlife
very distinct and accurate audio with unbelievable music
detailed world; water graphics; trip to and through barrow unbelievable
on master, very ez to die
great implementation of leveling what is used
very natural and accessible control/menu system
good looking constellation perk screen
some very boring, nondistinct and redundant perks
poor companion control; where's the companion content?

alright, time to start over and enjoy the beginning again!

Same here with the river current

You just got it yesterday? What are you doing on the forum?! Get back in there!

Some difficulties getting used to the new UI
The wonderful setting and art design
The music is even better than the last one
The water and the fishies

On my first playthrough I missed a lot of the beginning stuff because I was having issues with my mouse control that were irritating beyond belief. For example, I entirely missed that Ulfric was there! ha ha Once I got my controllers working properly things got more enjoyable.

One of the first things I noticed, and by far my favorite improvement, is multiple autosaves. I know it's so simple, but it makes a HUGE difference. I've lost a few characters due to the single autosave that I trusted. Never trust autosaves. Unless you're playing Skyrim. 'Cause there are 3! I quickly noticed that it was all the little things that made the game great. The main story and guild lines were all mediocre. Yes I enjoyed them, but they didn't last as long as they should have. But still.

i doubt you guys actually were noticing the big things like mountains and valleys. it seems more realistic that you were worrying about your inventory and what to do next and maybe running away from a fight or two.

For three hours?

I only had about a dozen things in my inventory.

You're describing hours 4-6.

I really noticed what most others seemed to, the beautiful water, the butterflies and the ambient sound. I also quickly learned that killing random street chickens is a hanging offense in Skyrim and vowed never to do it again.

I at first thought this was a problem with my graphics card or something. It is a really cool effect, isn't it?

First thing I noticed was the last three TES games start off with your character being imprisoned. =/
Then I noticed they made the argonians look a LOT better, then I found out dragons look great in this game. =3
First thing that really stuck with me, though, was the attention to detail everything looks so much more alive and believable. Once I started really focusing my attention on things in the distance I was pretty amazed, I play on a pretty nice gaming system so I could see trees on mountains that seemed miles away. It was then I knew that this was going to be an awesome game, even if it wasn't deep it was one hell of a world and the modding community wouldn't let me down. And I did have doubts about the depth of the game at that time since I had heard about it from friends, I didn't get it till it was on sale on steam.

That butterflies and Fireflies dies when you tried to catch them (I wanted to hold them and put them in jars, or collect a large quantity of them and set them free in my favorite grove/grotto)

The world was BEAUTIFUL!

The music was awesome... and intro very fittingly cinematic to set the mood and scene, before setting me free.

Hadvar. Just... Hadvar.

Doesn't really fit into the first 1-3 hours. But on all my new playthroughs I notice I always call out IRL to Lokir in a vain attempt to keep him from running.

The thing I remember the most about the first three hours was coming down the trail with Hadvar, he talks about "that ruin up there". I looked, and that was the first time I realizes how truly epic the scenery was.

Actually what really got me was the very first day I played (it was over Thanksgiving weekend, that's when I bought the game), by the time I looked around in the real world, I thought: "that CAN'T be the right time".. I had been playing for over 12 hours straight without realizing. I haven't done that on a game for a LONG time... not since 2000, when I first got Everquest.

How emotive the music was when you first come out into the world.

I liked him - he was the only one with the balls to actually try and do something about his circumstances, even if it happened to be the wrong thing.

I like to imagine my character was VERY passive-aggressive during the introduction.

Ah, a fellow TES fan who ruined a big part of their life with Everquest. =3

Idunno I have a lot of respect for that nameless stormcloak that stepped up to the chopping block moments before the dragon attacked.

And my character kept up with the lore so I already knew I would get out of it somehow. ~.o

Love how the exterior look cold and depressing and interior look so warm and welcoming. I love the rain/thunderstorm/blizzard and stormcall shout.