Xbox live

I have finally decided to get Xbox Live. The only question is, which one, the 12 month or three month subscription. I am going to be playing it a shit load during the summer and then every weekend during school and during the week and next summer, etc. Which one is the best value. I want the best experience possible?

start with a 3 -- if you overplay you might not be up for it after that or you might still be mindlessly addicted and go from there.

What's the difference in the online community? Will the full year give me more access to the Live community?