I've been hearing rumors of a new TTS album too, but the idea of their sub group was originally supposed to be Girls Generation - three letters. The group wasn't supposed to be TTS and then TTS again, next one was supposed to be three other girls!
If they make an English album with three girls I feel Jessica has to be in it, Jessica, Tiffany and Seohyun are the best to do that. Taeyeons English is fine though too so they could do it with TTS I guess.
- - - Updated - - -
http://www.youtube.com/watch?v=kBviE-SwwOE