The prevailing theory around the blog realm is that ATT forced Apple to reject the official Google Voice application. Of course, there's plenty if anger and blame from mobile warriors to go around here.
It doesn't matter if you're an iPhone fan or not. The simple fact is wireless providers are redefining what "open" means and Apple is using the lame excuse of the app confusing users as a reason for GV's rejection.
For whatever reason, GV app works with Blackberry phones on ATT's network and nothing was said about this.
I'm sure Apple went back to Google to ask them for a watered-down version a la Skype. I'm hoping Google sticks to its guns and say "go frak off!" and is now proceeding to develop the webapp.
If you think about it, this actually plays into Google's hands. As Google try to push Chrome OS, it truly takes the control out of the hands of ATT, Sprint, Verizon Wireless, and others. So on Onxo, you'll begin to hear a double dosage about Chrome OS and other webapp developments.
ATT, dumb, dumb, dumb...and shame on Apple for not asking its partner "why is it that it is okay for the GV app to be working on the Blackberry and not on the iPhone".
This is why ATT is so screwed once their iPhone exclusivity runs out.
Note: Once again, this is Apple rejecting Google's official Google Voice app for the iPhone, not a 3rd party development. Look for a jailbreak version on Cydia pretty soon.