I do think that Wilson has the potential to be a very productive NFL back. He has good size and speed, and while he should be used most outside the tackles, he has the ability to effectively run inside as well.
I have a couple problems with the Giants picking Wilson, though. The first is that the description I just gave you is more or less the exact same way one would describe as Giants number one running back Ahmad Bradshaw. It won't necessarily hinder his performance, but in general you'd like for your second back to be a change of pace. That's why the Giants held on to Brandon Jacobs for as long as they did.
Second, while the Giants were clearly trying to improve their running game (which ranked dead last in the league last season in rush yards per game), I don't think the actual issue was the running backs.
Yes, Ahmad Bradshaw was hurt for a portion of the season, and yes, Brandon Jacobs is just not good at football, but in my eyes the issue was an aging offensive line. For a long time, the O-Line had been a strength of the Giants, as it enabled them to run the ball on just about anyone. However, once the Giants let go of Shaun O'Hara, kept Kareem McKenzie and switched David Diehl's position for the third time, the line was not nearly as effective as it had been in the past.
Which brings me to problem number three. When the Giants picked at 32, Coby Fleener, Courtney Upshaw and Jonathan Martin were a still on the board. The Giants lost two tight ends to torn ACLs in the Super Bowl, and replaced them with a gamble they signed away from the Cowboys and a gamble of a draft pick. Trading for Keith Rivers was nice, drafting Courtney Upshaw would have been nicer, and again, the Giants need help on the offensive line.
As I said, I don't think David Wilson will necessarily be the problem, but unless he has a better season than those three guys and can prove that he has somewhat of a different skill set than Ahmad Bradshaw, I think he'll be a disappointment.