See the 2nd comment in the right-hand column.
(image courtesy of AndroidCentral.com)
Now check these out:
Both applications have been around FAR longer (the 2nd one even more so) than the I1. So how does Motorola define push-to-talk? It must not have anything to do with pushing something and holding in order to talk to somebody because both of those applications have enabled ANY Android device on ANY carrier to do so since they launched. I know what you're thinking, "but the I1 has a hardware button for PTT." True, and?
Admittedly I've never owned a Nextel so I'm not sure how the "traditional" solution works for phones (as opposed to radios), but it would seem to me that you're going to have to turn the screen on and select (or at least confirm) a recipient the majority of the time so what's the big difference between holding a button on the screen, and one on the side of the phone?
Can anyone explain to me under what circumstances Motorola has created the "world's first push-to-talk Android-powered smartphone"?
P.S. I use TiKl regularly and love it. I've used WalkieTalkie also and it's great as well, but for different reasons and those reasons are currently its weakness as well. I hope to see one of these developers combine the best of both.