If anyone is disappointed that TellyBean stopped supporting the camera directly connected to the Shield, apparently there is a new Android TV app, TrueConf, that supports them. Seems to work pretty well. Just had to lengthen the sleep timeout so the Shield wouldn't go to sleep while chatting. The app seems to have been around awhile, but just recently gained Android TV support.

https://trueconf.com/blog/press-release/trueconf-brings-4k-video-conferencing-smart-tvs.html

https://play.google.com/store/apps/details?id=com.trueconf.videochat