Google has silently release a new social networking site called Disco. It's not related to music, even though the background for the site is people are dancing.
This site offers Group Texting on Any Phone, so it's similar to RIM's BBM (BlackBerry Messenger), but it's offered by Google. There are several other providers such as GroupMe, Fast Society, KiK, and Beluga (now owned by Facebook), so they are having such good competition.
Unfortunately, this service is limited to US numbers only for now, so i don't have a chance to try this features yet.
This service is also available on Apple App Store