I hope this happens. But until then, I'm happy with Skype. If the iPad & iPod touch get front facing cameras (and microphones), then Skype could work on all iDevices, Macs, and PCs. That gives good competition to FaceTime.
I dunno, the problem with that idea is that it still shuts out Windows users... Unless they can convince the other providers to do that.
They could make FaceTime for Windows. After all, they made iTunes, Safari, and Quicktime for Windows. Do I see it happening? Probably not. I say that because iChat never came to Windows, so iChat never had a chance

At least for me, because I have very few friends with Macs.
How about linking it to your Mobile Me user name and make FT part of the premium offerings of the service?
Then you would have a lot of people complaining of that.
What's wrong with paying for things? If they did that, the Mobile Me service would almost be worth it for me. But even then, I don't think I'll be going back to Mobile Me. All I used it for was iWeb and publishing to Mobile Me. Then I discovered Rapidweaver & real hosting

Now my website rocks for half the price.
But you are right, a lot of people would complain. I don't see it happening though, as Skype would kill them, so to speak. As I mentioned, Skype will work for video chat on iPod & iPad if they get the front camera. Competition is good.