The complete triumvirate of next-generation gaming consoles is now available, but choosing the right system isn't as easy as going for the one with the highest rating. When shopping for your console of choice, here are a few things to keep in mind.

Go for the must-have games: Many games from third-party publishers--titles such as Call of Duty 3 and Madden NFL 07--are available on two or even all three of the consoles. But it's important to make sure that a must-have exclusive is available on the console you're buying. The Xbox 360 is the only place you'll be able to play Gears of War and--in 2007--Halo 3. There's a long list of Nintendo exclusives--including all Zelda, Mario, and Metroid games--that you'll find only on the Wii. The PS3, meanwhile, offers Resistance: Fall of Man, Untold Legends: Dark Kingdom, and Ridge Racer 7 (among others), but that list will flower in the months and years ahead with such titles as Lair, Metal Gear Solid 4, and Final Fantasy XIII.

Consider backward compatibility: Already have a library of old favorites you want to play on the new system? If so, you might want to avoid changing virtual horses in midstream. Some glitches notwithstanding, the PlayStation 3 should play nearly all of the games designed for the PlayStation 2 (and even the original, late-1990s PlayStation). The Nintendo Wii plays all of the games for the GameCube (you can plug in your GameCube controllers and memory cards). And the Xbox 360 plays many--but not all--of the games for the original Xbox.

You can buy only what's available: The newly launched PlayStation 3 is proving almost impossible to buy, thanks to very small production runs. And though it's being produced in greater numbers, the Nintendo Wii could be a tough holiday ticket as well. The Xbox 360, on the other hand, should be in plentiful supply, because Microsoft's had a full year to work out the kinks in its supply chain.