I would recommend that you don't get rid of the data corruption forum. It should be one that stands by itself for those cases where someone is really in need of recovering a corrupted databases.

Other than that, I agree with consolidating the groups as much as possible. Even to the point of consolidating the 2005/2008 forums instead of separate forums. Most of the functionality has not changed between the two - and, where a solution exists in 2008 only, the poster providing the solution can easily state that it is only valid in 2008.