Review time, from me. No spoilers, so safe to read.
I've played through the main campaign as my Wood Elf Marksman/Assasin/Thief, done all the guild lines, many, many quests (as many as I could find) and explored many-a-dungeon. I should make it clear that I love my RPG games - from Baldurs Gate through to the simplier Diablo.
But right now, having completed TES:O, I feel a little empty. I don't feel like saying "Wow, that was awesome, I'm gonna start again". I feel a little "meh". In fact, I can't see my playing through it again.
I think it comes down to the unsatisfactory nature of the levelling system, making quests and dungeon crawling feel a little hollow. The dungeons feel slightly repetative, there's very rarely any decent rewards, and I'm not going to find any real suprises due to the monster scaling. The same goes for quests. All you get is a few gold, and occasionally some decent items.
My main reason for completing the quests were purely for fun - which they were, the first time around. But most of the time all I got was gold...great, I'll add it to the pile of 50,000 I've already got with nothing to spend it on except the odd house. And yes, the Dark Brotherhood quests were fun, as were the Theives Guild. The main quest line was decent enough - the ending was certainly impressive, but I almost didn't get there as towards the end it became a real chore repeating yourself again and again for one part...I don't want to spoil it.
No memorable characters either, no one who stood out, all the NPC's were very 1-dimensional. The Radient AI was decent though, but mainly for comic reasons
On the upside, it had the most awesome world I'd ever seen - from the superb weather effects, to the day/night cycle and the landscape and views. Truely awesome.
Combat was frantic and fun, and worked well. Speechcraft part was poor, and the fact that even with security at level 10 I could get into any lock felt a little stupid.
I don't want to talk too much, this was meant to be an quick review, but overall, for me, it'll give it
85%. The levelling system cripples it for me - I had no feeling of power, no reason to explore that dungeon a little more, or no reason to go out picking fights on random creatures, and the quests lose their main incentive.
I'd be interested to hear other people's views, now its been out a while...