Banks like to use their own stock as currency for purchases.
Right now they can purchase assets on the cheap from the FDIC and other banks so they really don't need to buy the franchises to get the assets. They don't need deposits either, so they are letting deposits run-off and these factors lead one to beleive that we are still some time away from a bank buyout boom.
Now, when you see JPM and USB and WFC trading at 2 xs book, well that's when you will see banks buying smaller to mid regional banks that are priced at .7 - 1.2 xs book. It really does work this way.
The good thing is, as real rates continue to steepen on the curve, the lending for banks just gets more profitable. A lot of banks should report normalized earnings in the next few Qs and during that period of time you will see book multiple expansion (helped partly by the marking up of assets) and this will be a good bank to own in that environment.