The Brisbane L2 has alittle increase in latency compaired to the Windsor that gives the Windsor about a 1% increase in speed. The Brisbane is really no more than a die shrink from the Windsor from 90 to 65nm. But the Brisbane runs on alittle less voltage and runs cooler.
but at the same time, cache is decreased by half in the brisbanes, so in cache-excessive programs like encoding the windsor will actually win on stock settings
i have a brisbane and i can OC it it pretty far. i have the 3600+ model, its 1.9ghz stock, i had it running at 2.7ghz, which is a pretty nice overclock, but a ram upgrade has since forced me to put it back down to 2.4ghz