I took a few minutes the other night to cruise through the other servers and check out the Freeport population. None of the servers really seemed 'that bad'. There was a 3rd server that had just as much as Hodstock and CLW. I quit keeping track when I realized that even the least populated one appeared to have enough people to still be able to do most of the big Raids.
I dual-box a PS2 and a PS3. And I actually would say it does run better, even though there is only one aspect it really stands out...load times. Whenever porting, RH'n, or whatever...the load screen is about a good 5 seconds (honestly I think a bit more) or so shorter than on PS2.
On freezeups, aside from the known 'gnoll fort' problem and MTG problem, I'd say the PS3 would freeze/BSoD equal or less than the PS2. I'm pretty sure it's not more though. Last night was actually the first night I froze in a while (of course I rarly go by the gnoll fort, and (being bound in DM) I don't have much of a problem avoiding MTG.
Hope that helps ya.