Excellent game, but has little replay value
The world is gigantic and beautiful, there is not a single location that isn't worth taking a picture of. A little bit more variation would be nice, but it's still great nonetheless.
Every quest was interesting to follow and every conversation worth having. Especially the Dark Brotherhood quests. The best part is, I thought I had completed every quest in this game, but according to the wikia site I wasn't even half-way.
The gameplay is just excellent; comparing armor, fighting demons and sneaking around in dungeons, everything just works.
The DLC that comes with the GOTY edition is pretty sweet. The first one is just a new, epic quest-line for you to follow, but the Shivering Isles is the better of the two; a whole new interesting continent, new quests to follow and new scenery to admire. If Cyrodill is a beautiful, but standard painting of a meadow than the Shivering Isles is that same meadow after a radio-active-paintball match.
The game is full of glitches which sometimes come in handy, but are mostly just annoying. One time a guard followed me into the Oblivion realm where he kept picking fights with Demons, so I tried to help him, but the idiot jumped in front of my arrow and died. This was enough for the Bruma Guard to put a 1000 gold pieces bounty on my head.
The quests just aren't fun to do a second time because you know all the puzzles and twists already. The Shivering Isles even comes with an achievement that flat-out demands you play it a second time which is kind of stupid.
The Bottom Line
This is a very awesome game in which you can easily spend more then five-hundred hours. The quests are fun and the gameplay is great, but it has a few annoying bugs and glitches. This is also a great game if you want to get into (fantasy) RPG's, but if you don't like the genre you might want to avoid this game. Oh and before I forget: By everything that is holy, do not lose your saves, having to replay this game is a nightmare...