Through a recent Press Release, Yahoo has announced a new feature for its Yahoo Mail service: "the ability to send free text messages... to mobile phone numbers in the US, Canada, India, and the Philippines."

I don't mean to rain in on Yahoo's "look at what we have!" parade, but this announcement is also the perfect opportunity to mention that this feature has already existed on Yahoo Messenger for many months now. In fact, take a look at the IM client's online documentation:

You can send text messages to friends who have service with any of the following wireless carriers:

USA: AT&T, Cingular, Verizon Wireless, and T-Mobile
India: Hutchinson, Airtel, Spice, Escotel, and Reliance
Singapore: Singtel
Thailand: AIS and DTAC
Malaysia: TMTouch
Philippines: Smart and Globe

That's right, Yahoo Messenger actually lets you send text messages to even more countries than the new Yahoo Mail. And both apps are based on the same business model: let users send out SMS messages for free, and charge anyone who replies to them with their mobile phone.