via MLBTR
As a Jays fan I'm shocked and conflicted. Marcum has had 3 very solid seasons and really looked like a great pitcher last year, and somebody who wasn't going to cost incredible money to keep around. His success came from his command and mixing up his pitches, it was awesome to watch him strike out hitters like A-Rod and David Ortiz with 86mph fastballs that they didn't know were coming. Guys like that tend to age well. By all accounts he was the leader of the pitching staff and a great teammate.
But on the other hand, he's 29 years old and only under team control for 2 more years. Lawrie is one of baseball's 50 top prospects, and outperformed guys like Dustin Ackley in AA even though he was 2 years younger. He has a special bat and is still learning how play 2B and commit to defense. Reports say he doesn't have a great 'body', but did steal 30 bags last year.
The Jays definately have a surplus of quality starting pitchers, but it remains to be seen how trading away the leader of the group will effect the rest of the young staff.