Everyone, be careful! There's a MSN virus about

Hey all, just thought I'd advise you all to be vigilent.

A few minutes ago I received a message from a friend (who was obviously infected with this virus) asking me to check out a really funny link.
I clicked it, and loads of msn windows started opening.

I soon realised that the link was a virus. The link was to a website, which address I cannot remember, but the filename was:

Cute.pif

Anyway - this has effected a lot of people on my msn list - and is spreading extremely quickly. Has this happened to anyone else?
I have Norton AV and Firewall 2004 with the latest definitions, and it found nothing on my pc - nor did Microsoft AntiSpyware.

Could this be a new virus to which the virus definitions are unknown by the virus scanners?