After updating to 1.6.1 my fps has dropped from roughly 80 to 10. It does the same thing on both single player and multi-player When using the old MC launcher FPS rates return to normal. The computer only has an integrated graphics card.

Computer Specs (Laptop)
Windows 8 (64 Bit)
Intel i7-3632QM CPU @ 2.20 GHz
8 GB RAM
Intel HD 4000 Integrated Graphics