UPDATE: Republicans officially control 30 state legislatures (31 if you include Nebraska), Dems only 11

While Obama doesn't believe that he is responsible for the latest wave election, Republicans are more than happy to give him the credit (though presumably they would have preferred never having the damage done to the country to begin with).

To see how dramatic the change has been note that this change flips state legislatures that weren't flipped after the 2010 wave.  The new state legislatures controlled by Republicans are:

Colorado Senate (conceivable that Dems could still hold on after recounts)

Maine Senate

Minnesota House

Nevada Assembly

Nevada Senate

New Hampshire House

New York Senate

New Mexico House

Washington Senate

West Virginia House.

West Virginia Senate (after Democratic Senator Daniel Hall switched his party affiliation to Republican).

Legislatures: 30 R, 11 D and 8 split (Nebraska is technically nonpartisan, but is really controlled by Republicans so that would really make the total for Republicans at 31)

Chambers: 68 R, 30 D

Governors: 31 R, 18 D and 1 undecided (Alaska)

State governments: 23 R, 7 D, 18 divided and 1 undecided (Alaska)