I have no problem with it at all. The object is to score after all, and you should be able to use any means necessary. It's similar to when a catch was still ruled a catch even though the receiver was pushed out of bounds if by the official's judgement the receiver would've got two feet in. The defender should have any means necessary to force an incompletion by pushing a receiver out of bounds and I'm glad that rule was changed. If the NFL outlaws the Tush Push it won't bother me at all, but I have no problem with it. If anything, you should only use the Tush Push on 4th and goal from the 1 yard line.