User blog comment:LoveWaffle/Galactus is Coming/@comment-4276072-20120806225831/@comment-1895174-20120806233735

Since Thanos is more or less the confirmed villain for the Avengers 2, I think the main purpose of the Guardians of the Galaxy movie is to introduce him to a mainstream audience. After all, including the Guardians as main characters in Avengers 2 would make the main cast WAY too large.