Should i upgrade to the iPhone 5? I have the 3gs?

First of all, i'll ignore the " don't get the iphone, just get an android blah blah" i'm getting an iphone for reasons.

anyways should i? I'm eligible for an upgrade if i get a 2 year agreement. But if i do, id have to wait 2 more years, and i new one could come out soon.

should i wait? My 3gs works fine, except for the home button and silent switch, but it works with assistive touch.

so should i switch or not?

No you should not switch right now. You seem perfectly fine and happy with your 3GS. When talking about apple timing is everything. You have waited this long might as well wait a couple more months and get the iphone 5s. It happens every year and it is a wiser investment. Nothing is worse than getting buyer's remorse.