If you are a Gmail user, you should be seeing a new Labs message as shown above. This is one of the best SMS solutions that I have seen and used in a while.
Of course I am more interested in the technical aspects of the endeavor than the final results. The management of the messaging is done very well and I really hope that this feature sticks and exit Labs to enter the mainstream.
The messaging with Chat feature on Gmail is great for a person like me, who is constantly online and my Gmail is always on. And I do not like to type on my phones, does not matter what they are, Androids, iPhones, smartphones with one exception, Blackberry. I can type on a Blackberry a complete email message without any problem. It could be because I am used to it for a long long time.
Anyway back to SMS Texting with Gmail, The user may find that her/his contact has walked away from the conversation before she/he could give the final, important message, instead of switching your communications methods like looking for phones, now you can continue to chat in your Gmail Chat window. You just send the messages to a phone number!
The phone will receive a message from a number with prefix 406 (G0O), and users friend contact can reply to the message as to any other message. Google machinery in the background will route the messages back to original users chat window. The massages from the same user will have the same number. So you can save to number in your phone.
Suppose someone started to spam you or you do not want messages from that particular user, just send "BLOCK" as a reply to the message. If you want to stop messages from Gmail altogether (DON'T) you can reply to the message with "STOP" and Google will honor your wish.
Official Gmail Blog: Really new in Labs this time: SMS Text Messaging for chat
Thursday, December 11, 2008