If you found GTA:IV lacking...
If you were pissed off by a lot of the stuff that didnt make it from GTA:SA to GTA:IV, this is the game for you. Saints Row 2 takes all those wonderful side things to do and expands on them and evolves them.
You can buy properties, take over gang turf, customize cars (in meaningful ways too), customize your gang, buy clothing, all the fun stuff that GTA:IV lacked.
By far the best improvement over the GTA series is how this game handles cars you own. Instead of find a great car then parking it in your driveway and being afraid to ever drive it again, this game has a garage where you can "save" any vehicle you like. Once saved, you can get it out at a garage at anytime. You can use it on missions without fear of losing it, blow it up, or just drive it into the river for fun. There is a fee to have it repaired, but its small enough that you wont care.
There is even a phone number you can call to have any car from your garage delivered to your location, this can be a real life saver if a mission has gone tits up (has to be unlocked).
You can also customize any car, with not only cosmetic upgrades but ones that enhance the performance. My favorite is the chariot style spikes you can put on the wheels to pop other cars tires as you drive by, makes "chase" missions a breeze.
For me, its between Saints Row 2 and Fallout 3 for game of the year 2008.
