Bourret is also older - pretty much the oldest draft eligible player who didn't opt out of last year's draft. As such, he's a bit more mature and his production should be a bit higher (Bourret us about year older than Crosby and 9 months older than Latendresse).
I think their offensive upsides are similar, but Bourret seems the safer pick and probably will take a quicker route to the NHL. Actually, he might be one of the players to crack a line-up this season. Latendresse however, may be just as much the player Bourret is and the better long term power forward package, it'll just take a lot longer. And with the higher risk, comes the lower selection most likely. But his upside is such that he probably won't last that long past #15 (if at all).