For me, the sheer amount of locations you can discover, the open-ended aspect of the game and, a beautifully crafted world is more then enough. It is a great playground to do whatever you please. When I go into Skyrim, it is easy to get absorbed and forget about mundane worries. This is the biggest draw for me.
I really don't mind the occasional bug. In my experience, they are hardly game-breaking and at least for PC, they've been easy to fix. I can't wait for the CK to come out and start modding my game as desired and download other people's creations to enhance my experience.
I've put over 165 hours and still going! In my main character level 53 I still haven't discovered all of the locations and going out to explore is my favorite thing to do. I haven't touched the College of Winterhold, Bards College and the Companions questlines yet, but I've done the MQ, Dark Brotherhood, Thieves Guild, about half of the Daedric Quests and, most of the prominent sidequests. I still have a ton of Misc quests andf I've tried about 4 different character builds: Thief/Assasin, Conjuration Mage, 2H Battlemage and Sword and Board.
If there's some complains I have about Skyrim is some of the less useful skill trees, some short questlines, Smithing (you have to agree, it's insanely fast to level and makes any other loot completely irrelevant), repetitive one-liners, slow and plain bothersome Companions, small cities (villages, really), clunky horse riding, the interface,and, the absence of features of other ES titles (like spellcrafting).
Even thought Morrowind holds a dear place in my heart, as I poured hours and hours into the game and found it way deeper than anything I've ever played, Skyrim is well-made, fun, gorgeous and, definitely my favorite game of the series.