I have the same problem and have been unable to find a solution. I run Chrome on two Macs with 10.6 and it's great. I have a Mac Mini running 10.7 and Chrome is completely unusable. I've switched to Safari on that machine, but I test Chrome every once in a while and as far as I can tell things are getting worse, not better. Initially, it was just very slow. Now it hangs and crashes.
That machine has 8 Gb of memory, compared to 4 for both of the others, so that's not the issue. Someone suggested turning off the pre-fetching, but that didn't help. There is also a beta release of Chrome called "canary", which runs no better and has more bugs.
It's hard the believe there's enough difference in the operatings systems to cause such a degredation
in performace, so I'm sure it's something very subtle and silly, but as far as I can tell, no one is working
on it very hard.
If you find a solution, let us know. I really prefer Chrome.
-Eric