Based on this list [wikipedia.org], it looks like merger activity between US banks dramatically slowed since Obama took office, after going through the roof during the Bush years.
I counted 48 mergers during the Clinton years versus 39 during Bush.
Well, shit, when an industry is consolidating of course there are going to be a bunch of mergers (of small companies into medium companies) at the beginning, then a moderate amount of mergers (of medium companies into big companies), then just a few mergers (of big companies into gigantic, dangerous ones).
So yeah, we should fully expect Clinton mergers > Bush (II) mergers > Obama mergers, just because by the time Obama got in office there were hardly any companies left to merge!