I think the job is Quinn's to lose. He's been their "quarterback of the future" for some time now, and he has every chance to prove it right now. I don't think the decision is made yet though - He may be taking the reps with the first team, but someone has to, right? And like I said, he's the "QB of the future" so he has the early advantage. Watch how preseason games go. If Quinn does poorly, I expect Anderson to start the next preseason game to see how he runs the offense. It's far too early to make a real decision about this, but I do think Quinn will end up starting in Cleveland.
As far as trading Anderson (assuming Quinn is firmly entrenched as starter).... I guess it all depends upon how much the coaches like Ratliff. He's clearly an unproven prospect, and I don't know all that much about him. However, he is a guy that Mangini specifically wanted, so perhaps he's pretty decent.... however, you'd think someone pretty decent would have beat out Kellen Clemons, right?
Teams always want a solid backup, and the Browns have one right now, no matter who wins the job. However, if they do decide to trade Anderson, what would he be worth? Matt Cassell was only worth a 2nd round pick, and he hasn't shown the penchant for turnovers and innaccuracy that Anderson has shown. So would it be worth trading him for a 3rd or 4th round pick?
And also, what teams would Anderson really be a huge upgrade for? (ie-one that would be willing to give up an early-ish pick as well as pay him a fairly bloated salary). It would have to be a team that is built to win now and is facing an injury at QB and has no backup plan because I don't see any teams treating Anderson as a legitimate starter. The Texans could be logical - they have the often injured Schuab, and Dan Orlovsky is thier backup. The Bears really don't have anyone proven behind Cutler, I don't trust any of the Falcons backups either.
I think it would take a pretty unusual set of circumstances for a team to trade for Anderson. The trade deadline is week 6, and normally a team will give their backup a game or two to see how they do. So you'd be looking at a QB getting injured within the first 3 weeks or so on a team that thinks they have a legitimate shot at the playoffs right now. Then they have to decide that it wants Anderson rather than some of the serviceable free agents still available or some of the other QB's who may be available for a trade. It's not impossible, but I don't see it happening.