There's too much talk especially emanating from Cleveland for me to not believe that Mallett will not eventually be traded there.
It makes sense for both teams. Cleveland needs a QB to compete with Brandon Weeden and picking 6th overall is a little too high to draft one in the first, and they don't have a 2nd rd pick. For the Pats, Brady is signed up for 5 yrs, and Mallett isn't exactly the ideal backup for him because their games are significantly different. Plus, the Patriots could use a few more picks in the 2013 draft.
Sending Mallett to the Browns long with the Pats 3rd rounder and Bucs 7th rounder for the Browns 3rd, 4th and 6th round picks in 2013 plus a conditional 2014 or 2015 pick which based on playing time and performance could be as high as a 2nd rounder in 2014 or a 1st rounder in 2015 (Pats option) sounds fair to me.