I believe one of the biggest reasons why the U.S. is behind in mobile technology is due to the large control imposed by the wireless providers. They disable hardware features (ie. bluetooth, wifi) and set software limitations just to squeeze an extra cent out of their customers. This ultimately hurt the consumers and the mobile movement as a whole.
The latest story came from customers of Sprint PCS. Apparently, users of the Treo 700wx have been having some difficulty in sending SMS text messages to Verizon Wireless and T-Mobile customers. Perhaps this is just a simple mistake and Sprint is working to fix this problem. I wouldn't be suprised if this was done intentionally.