Judge Nap says that if the GOP were to take the senate they could reject regulations while they are in the (30 day) review stage (they cant do anything about regulations that have already taken effect, however).
5:45 Minutes
Judge Napolitano: EPA Colluding With Environmental Groups To Shutdown Coal Industry
http://www.youtube.com/watch?v=2Q9Pn_vokho
Judge Nap indicates this veto vote is different than legislative veto - this vote invalidates regulations or takes regulation proposals off the table.