The official site for Transformers: Dark of the Moon The Album and The Score has launched at Transformers3Music.com. Right now there isn't a whole lot to it. It has the Optimus Prime banner (but slightly altered) for background, lets you pre-order the albums for the June 7th release date. As with the previous two films, The Score was composed by Steve Jablonsky with an assist from Hans Zimmer.
It also lets you hear a sample of the DOTM remixed version of Iridescent that is the first single to be released from the album. A source that has provided accurate information in the past provided me with a copy of the song and it does match the version that was posted on Soundcloud last month. Amazon lists the single release date as May 17th but other sites have different dates. (via TFW2005, thanks to Sahara for link)