Finally went format neutral with a PS3 yesterday, got tired of waiting on the Sammy up5000. Everything is copacetic, but the manual is a bit sparse on the whole web surfing thing. I'd hate to get malware'd right after dropping 400 bones on this thing.

Anyone know if the thing at least uses a firewall while connected?

The PS3 uses the firewall in your router. If you have it running directly from you modem then you don't have a firewall, but it's not Windows based so there is no ActiveX so you shouldn't have an issue even if it is. I've never seen or heard of any issues with malware on a PS3.
Anybody else?

I don't worry about protecting the PS3 from malicious code. The PS3 doesn't run unsigned (i.e. homebrew) code. This is seen as the 'holy grail' for hackers and pirates alike. So unless Sony releases a 'signed by Sony' PS3 worm, my PS3 is safe. There isn't even a modchip out for the PS3 yet.

If someone can get my PS3 running homebrew (not under Linux), let me know.

If you are running Linux that's a different kettle of fish. You have to protect it as you protect any computer. Either run a firewall under Linux, or put it behind a NAT router (i.e. Linksys or whatever).

No issues with security here.

didnt sony add anti virus protection in firmware 2.0 I think its free for now but will cost to renew in the future.

Excellent Thanks Fellas!