It will be a hugely positive event if Devin Thomas plays the way a second round draft pick is expected to play. Please drop any expectations that he is another Calvin Johnson. That would be a gift from the football gods were it to materialize.
One cautionary note, however:
Talk is cheap. He had a full year in 2008 to show his talents and his desire - - and he didn't do it. Now he is talking a good game. What matters is that he takes all that "talk" and translates it to the practice field such that the coaches believe that they can depend on him sufficiently to have him on the field for 75% of the offensive snaps when the games count.
Anyone who can type can start a blog and say all the right things. Not everyone can take it to the field in the NFL... Recall that Brandon Lloyd said lots of positive "stuff" in his offseason here and it didn't amount to a pinch of pigeon poop once the real games started!