Even though the first ones haven't been released yet, and my hope was these wouldn't be popular enough to see more released, 2 more have been listed on an online store - Jazz and Shockwave. No pics though, but those who are familiar with Mighty Muggs will know what to expect...
http://www.play.com/Gadgets/Gadgets/...z/Product.html

http://www.play.com/Gadgets/Gadgets/...e/Product.html

These two aren't due for release until June, and are listed as Wave 3, so maybe the first wave is still some time off as well.
I wonder if the four already known (Op, Meg, BBee, SWave) are two waves or just the first wave.

Oh heck... I just checked and those four ARE wave 1, and Starscream and Grimlock are wave 2...
http://www.play.com/Search.aspx?sear...arch&pa=search

I'll try to contain my enthusiasm...