I think this is a new feature in the iPhone 2.2 software that nobody has come across of and I think it could be useful. It is a new behavior of the keyboard and I cant really explain it so here is a video on how it works and what it is.
http://www.youtube.com/watch?v=ItQowP7PjZo
http://www.youtube.com/watch?v=ItQowP7PjZo