Obviously there are markets for the technology, but they aren't huge and with the existing limitations it's not nearly as easy as the commercial makes it seem. The soldier doesn't have WiFi (or money for two iPhones). The hospital doesn't either for that matter. Grandma and grandpa would have to setup a wireless network before being able to see the granddaughter graduate. At least with my grandparents that means you have to set it up and then fix it every time you visit. The deaf demo is the most realistic, but it can be hard to sign with one hand so a laptop with a webcam will work better in many situations (or frankly just SMS/IM).

Even with the Face Time technical limitations, the lack of video calling isn't a technical problem but a social one. I've had a laptop with a webcam for 5 years and used video calling a handful of times with at least two of them being just to get screenshots for a book on OS X. It makes a great demo, but at the end of the day I almost always prefer text to audio and audio to video.