Howard Rheingold asks "why aren't Americans using phone texting?"
I believe that the preliminary reason why people are having such a hard time adopting this is that they really dont know about it. I know that AT&T just sent me a message to let me know that text messaging for the entire month of December is free, which would indicate that they see the potential for this technology and are encouraging people to start using it.
The other big factor is just the usability factor. To be honest with you, I dont text message anyone that isnt setup in my MSN instant messenger, because it is a collossal PITA to punch out a message of any real value using a telephone keypad.
Of course, I could use Outlook to send an email, but the email address format is different for every service provider. It's hardly effective for me to maintain a list of service providers for anyone that I may be interested in sending a text message to.
Until a more unified and simple system is in place to facilitate the sending of text messages, I dont believe that this technology will really take off.