FPS Drop since update

Since updating Minecraft to version 1.7.3/1.7.4 the game has become incredibly choppy and unplayable. The FPS jumps from the usual 60 down to 5-9 while playing the game. I am playing on a Mac running 10.9.1.

Reverting back to 1.7.2 has solved the issue, any version newer than that has the FPS drop issue.

Thank you.