It would be useful if they you reached a certain amount of upvotes you can get into the marketplace too. That'll help with actual contributing users that don't post much. The current system provokes people to just post quick short responses to raise their post count.
I agree that there should be something to come from the votes...However I can't agree that the current system provokes short quick responses. No matter how many posts you have you can't view Marketplace until you have been here 6 months. I rarely post here, but I have gone way over the minimum number of posts, and I still have another month to wait.