Britney has been smart since the end of the FF era. She was never out of the public's eye/ear with stints like XFactor, a smash hit with S&S and was part of a huge movie by penning a song for it. At the same time, she's been releasing info little by little and the hype is self churning without her even releasing a lead single or even an announcement of it.
Beyonce, on the other hand, slammed the public, since the Super Bowl, with her impending return. However, as of late, interest for her forthcoming album has been dropping with her only releasing snippets and running away to Europe to tour. I think the last straw was the verified news of her pushing back her album yet again to a later date.
With all this in mind, the tides have turned and Britney is once again at the top of the most anticipated list for the GP.