D-League players, and maybe 2nd Round draft picks looking to make an impression before camp opens.

I am not sure which way college football would go. I mean I can see both ways. The reason college football may not oppose it is if the NFL adopted the same rules as MLB (drafted straight out of HS or 3 years in college). College football has already pushed the envelope where people are starting to look at some aspects (i.e. amateur status, the real reason players are in school, etc.) of "big time college football" as being a joke. It is also possible that colleges are getting closer to a fork in a road where they will be forced to decide whether to make football a "pro league" or return to a more "club-like" status.

The MLB rules would allow schools to take a step back or at the very least maintain a holding pattern because the players that pick college will be there long enough to obtain a degree. Also, it could make it easier for the NCAA to change the bylaws to make it easier for schools to seek reimbursement for athletic scholarships where the student-athlete doesn't maintain a good academic standing. If the schools and the NFL continue with the status, then there is the possibility that Congress and/or a federal agency could mandate change which neither party may support.