Why, Blog, Why?

So, I've had an Xbox 360 in my possession since late-Spring '06 and the only game that I currently own for it is Oblivion. Not that I haven't gotten my money's worth out of it (1000+ game saves and over 300 hours of play, and still going), but it's not multi-player and I miss hopping on line with the old Gamertag.com crew. I hear Gears of War is a good time, but I don't want to run out and buy a game that everyone else will grow tired of and stop playing in 3-weeks (which is what usually happens). So, if any of you have suggestions for an upcoming game that might have some longevity, I'm all ears!