Alright, I'm not sure if it was ever posted here or not, but was a second wave announced and if so was there any word on who was in it?
Grimlock, Hot Rod, Arcee, and Thunderhowl all came after wave one. I thought they all constituted wave two, but according to tfwiki the latter two are wave three and four, respectively.
If you mean the next lot (given that all 8 of the first officially announced lot have been released), then we know (or think we know) that there are at least three more on the way - Prowl, Starscream, and Soundwave.