Firefox4 is faster than chrome here on ubuntu lucid x86_64 on an i5 with 8g of RAM.

Results for firefox 4 beta7:

http://krakenbenchmark.mozilla.com/kraken-1.0/results.html?%...

Results for chrome 7.0.517.0 dev:

http://krakenbenchmark.mozilla.com/kraken-1.0/results.html?%...