Don't just go by the system alone, look at the games that will be made available and also the companies that will be making the games for the console. Reason why people are faithful to Nintendo? Because Zelda rocks. Why do some swear by PS? Ummm... ___. And Xbox? Halo. Bluh bluh bluh.
You'll be playing the games, not the console, so look at the games and think what genres you like and go from there.
From a technology/architectural standpoint, PS3 looks friggin' amazing.