Do you have Optifine installed? I use Optifine and it really helps! Optifine also gives you more options like autosave time, more control over animations (particle and water/lava etc.), Sun and moon etc. I used to have to wait every couple of seconds for the fps to go up but now I can zoom around in my MC worlds, the only thing I have to look out for is my PC over heating! ;)
P.S. I use a PC w/ 4 gig RAM :D
