Got PIAF purple installed and patched over the weekend. Setting up two of the 1535s to register and do video calling was pretty trivial. There's a little bit of lag in the video but it's not too bad. I also called the test numbers and there was no problem with the audio quality. Nice and sharp without drops, latency or jitter. This is running in VirtualBox with the extensions installed on a Pentium dual core. I've assigned 1gb of ram to the VM.
To turn on the video capability you have to add the following to sip_extensions_custom in the asterisk directory:
videosupport=true
allow=h264
allow=h263
Don't forget to reload the configs!
Next up is getting Google Voice to work.