I had the same problem, i had kernel panics almost every 10 minutes. i tried getting my macbook repaired by apple but my macbook was too old for the 3-years replacemend program.
As a last resort before ordering a new macbook pro i tried reflowing the GPU on my 2010 i5 macbook pro... And it worked like a charm! Since reflowing the gpu, i experienced zero kernel panics. So, before sending in your macbook to replace your GPU, try reflowing. Just dissassemble your macbook and take your motherboard. Remove the cooling paste, heat your GPU to the right temperature (see nvidia reflow profile(http://www.ifixit.com/Answers/View/131448/Nvidia+320m+reflow+profile)) and assemble your MBP.
Good luck!