GOOGLE ANNOUNCED Thursday that it has started rolling out an SMS messaging feature for its Gmail web-based email users.
The SMS function is enabled through Gmail Labs, which is accessible via a tab on Gmail's settings page. The SMS interface runs in Gmail's chat window on the left navigation pane.
To send an SMS message, the user just types an SMS-capable mobile phone number into the chat window. That triggers a Send SMS pop-up menu.
Google assigns each Gmail SMS user a persistent phone-like identification number so that SMS recipients can send SMS messages back to the Gmail user later.
SMS messaging is just the latest of Google's Gmail Labs toys. In the past month, Google has launched seven new Gmail features, including Gmail Gadgets, message emoticons, Gmail for mobile 2.0, canned responses, new contact manager features, advanced IMAP controls, and Gmail Goggles. µ
L'Inq
Informationweek
Don't think is available in the UK yet!
Thanks for the article. the service is only available in the USA at this time. I am in canada and its not an option yet. You will not get the tab for sending text when you type the telephone number in the chat box and it can not be added from the "lab" tab. Not sure when it will become available but would certainly be interested to know. Thanks
"Google SMS is currently not available in the UK." -
http://www.google.co.uk/sms/
Only for American phone customers.

Awwwwww I'll have to wait before google can customize adds specifically from my sms chats 

*sad face*