Hey I got the alpha version on two macs, and the beta PC version on two pcs and tested a 4 way video conference with it. The host Mac is mine which is a Macbook Pro Laptop 2.16 GHZ duo core. The other mac is a mac laptop, forget what my buddy's got, then two IBM thinkpad R51 and R61 laptops.
It worked pretty good other than some issues on our end which is was due to mic and speaker placement. With the delay of the video conference, we were getting echos back from peoples computers. We have started to solve this problem by using headsets with and without microphones that has solved the problem of the audio echo. We are going to do another test tomorrow sometime so if anyone wants to join in my oovoo account name is Philoett.
Have not noticed any problems with the mac alpha version as of yet. Along with the 4 person video chat, I did do a 1 -1 mac to mac chat, and a 1-1 pc to mac chat, and they worked well too. Let me know if there is anything else you want me to test.
Phil