Like the others have said, SIP video works fine if the PBX supports it. Your SIP provider may not so mileage may vary. I have my own Trixbox/Asterisk server and have tested video with the N800 and various SIP clients on PCs. It works peachy although there aren't many other people to connect to outside of users on my own PBX. Video conferencing has been around a long time and never took off but it does work. I hear that the few video phones out there like the Grandstream work well with the N8xx over SIP.