After I've been playing Minecraft for an hour or so, it starts to pause for about 15 seconds every few minutes. I have got used to just quitting right out of Minecraft as soon as this happens and re-loading it and that cures it. Any ideas? I'm on a Windows 7 32-bit Intel Xeon 4-core laptop with 4GB of RAM and Java 7 Update 6.
Its a problem with the coding not being optimized and probably your video card/cpu heating up and collecting lots of data from playing so long. Jeb said he will be focusing on the minecraft engine more now, so hopefully these lag spikes will stop. It happens to me all the time and I barely play anymore because after 1.2, I get horrible frame rates.
http://www.youtube.com/user/pancakesimone