How many servers does this site uses you think?
 

http://www.gofish.com

Is it possible to run it on 2 servers?

A huge web one with 4 gig ram and a huge media one. I know it depands on traffic so lets say 300k.

i think it really depends on the software they are running, the amount of vids they are serving each day and the patterns of traffic.

i knew a company that was doing 128k streaming audio that was doing 2 gigs per second and they were using 80+ servers. not sure on their daily users.