Check out Britney performing 'Hold It Against Me' LIVE in San Francisco on Good Morning America.

I think Brit is officially BACK and ready 2 TEAR SHIT UP... Gaga Who?

The performance is flawless and her voice sound AMAZING. You would NEVER GUESS that she had 2 kids based on her sexi, sexi outfit.

I lovelovelovelovelove Brit. #notagirl_notyetawoman

U look HELLA GOOD, bb! #Federline_Who? IT's #Britney_Bitch