SMS in US

After reading Kiruba Shankar's blog today, I wonder where does SMS stand in US. It's not that popular here like its in Europe and Asia. US is 3-5 years behind Europe in the usage of SMS. There are many reasons for low usage of SMS in US.

The foremost being the lack of inter-carrier interoperability; unlike European countries operating on single GSM standard, US carriers are following many conflicting standards(CDMA by Sprint PCS, AT&T follows TDMA and VoiceStream has GSM). Another reason is that people in US pay per-minute charges for mobile phones usage(to make a call or send/receive a text message), whereas in Europe/Asia subscriber is charged for the number of messages sent. Third reason I can cite is the Generations X's and Y's in US has not got involved till now(for whatever reasons, IM??). Then there is Instant messaging and two way paging, which is more popular in this part of the world. Americans are more into small gadgets(the Blackberry and Motorola etc) then tapping short messages on their mobiles.