As a professional 3D-artist (11+ years in archviz) Skyrim is a masterpiece in regard of graphics IMO. It doesn't need all the latest shaders or ssa to look amazing. The design makes up for it. Few games allow the player to stop and just enjoy the vistas for a while and Skyrim is full of such moments. The scenery is breathtaking at times (PC) with the volumetric fog in the distance hugging the landscape, snow blowing around you and following the geometry of the landscape. Amazing! Too many details to mention here but it's a huge improvement over Oblivion to say the least.
On top of this the music is once again done by my favorite composer Jeremy Soule. Thank God for that because TES would never be the same without it. His music is what nails the magic atmosphere of TES that is consistent across all the latest titles. It's what makes the battles epic, landscapes majestic and the dungeons creepy. This time I feel the game is worthy of his music. Who can forget the music from Total Annihilation? Jeremy Soule is the gaming industry answer to John Williams.
Apart from being a piece of artwork, the gameplay is second to none. Bethesda is the father of the open-ended / sandbox concept. The gaming world feels vibrant and dynamic, and even more so with the radiant quest system that is new in Skyrim. People can play for days and never touch the MQ. That says a lot.
OK that's it. Got to work for a few more hours and then it's back to Tamriel once again. By Azura!