Liriano is universally held as a top pitching prospect. This is because he has the tools and ability to become one of the best starters in baseball. He has, however, a pretty rocky injury history, and has the risk that comes from being a young pitcher.
Right now Liriano's value is just about as high as a (non-Felix/Prior)pitching prospect's can get. If you have Liriano, do you trade him while his value is high, or do you keep him in hopes of his becoming Jake Peavy/Johan Santana-lite?
I guess this is a question of pitching prospects vs. position prospects. If you can trade Liriano for a Daric Barton/Brandon Wood mid-tier blue chip prospect, do you do it? Or would you rather roll the dice and hope Liriano comes up a winner? Who's an example of the lowest prospect you might trade him for?