Well, it wouldn't surprise me. The "no disintegrations" line suggested that Vader was familiar with his antics in some way. Maybe it's less of a friendship, although I do wonder what will happen to Boba after Episode 2. If the rumours are to be believed, he'll be flying Slave 1 away by himself or he'll probably get picked up by the Jedi. I'll scream if someone quotes some EU story where Vader's pet dog got disintegrated by Boba Fett, and that's how they know eachother.
How does SW disintegration work anyway? That droid in Jabba's palace pointed to another droid being pulled limb from limb, but that was hardly disintegration. I can't really see Boba Fett becoming a bounty hunter in the remaining films. If he's 12 in episode 2 and episode 3 begins from the cliffhanger ending of episode 2, he will be way too young.