Blah Blah Blah is rubbish and it's destroyed Ke$ha's momentum. She could have had three consecutive #1's with Tik Tok, Your Love Is My Drug and Take It Off, in that order.
The song is not going top 10 on the Hot 100 cause radio is afraid to add it at the moment. ITunes is clearly showing people still can't get enough of it. But radio is still playing TT, & they are reluctant to drop that so fast.