I wouldn't be opposed to Family Guy eventually getting that slot, but it'd be insane if Futurama did. For the last time, people, the show was never or never was going to be the "next Simpsons." Get over it.
I was never looking to label Futurama as the next Simpsons, but it was a damn good series in it's own right
As for Simpsons, I've seen maybe two or three episodes since '01 (last good episode I remember was the one with NSync and knocking boy groups), since it seemed though that the show was becoming SNL with a new guest star every week
Simpson character: "Oh my god! It's (Guest of the Week)!
So (Guest of the Week), what brings you to Springfield?"