Yep, this is such game. Good, long, nice to look at....yeah baby....
Since Gamespot has a good and big review about this game, I'll try to not retype theirs in worse language, but just to point out the best parts wich I think are worth mentioning.
First of all, if your a fan of the series, you'll be playing it now. You may not think it's the best game in the series, but you'll be pleased.
Second, if your not a true hardcore fan, and you can't really compare this game to it's predeccesors, you'll love this game.
The story is as lovely as a RPG can get. Rich, bold and nicely fit in the world of the Elder scrolls.
The good part of Oblivion(and Morrowind) is that you can do what you want. You can start the main quest and story, but you can also delay that for days/weeks/months, by just playing dungeons, side-quests and messing around with mods.
The graphics are well known. While my PC version has better graphics then my 360(my PC is insane^^) the 360 version is still very VERY good looking. I'm playing the 360 version with a VGA adapter on my 19 inch flatscreen LCD monitor and it rocks. The graphics and art style are truly amazing.
The gameplay is great, it let's you choose to play melee, range, magic, a bit off all, you know, open ended:) The fights are very cool, you'll feel every block, hit and smash while your fighting your opponents.
The sound is also very next gen imo. On my 5.1 headphone from Zalmann it's very nice. The sound effects from birds, batlle, water, you name it, are very well done, and you'll feel like your actually there.
Bad parts?
The bugs. But hey, if you played and loved the Elder scrolls like I did, you are allready used to those bugs:P It's still bethesda!^^
Conclusion:
If you like open gameplay, amazing graphics and realism, rpg and ofcourse hack&slash rpg battles, look no further...crank this game in your DVD or 360 and play on, it's really that good.