There was a good 4 years between 1 and 2, so it'll probably be some time before we get 3, but I imagine we'll get it at some point since it's a pretty popular series. I hope so anyway, since Rinko is mai waifu. If there's one thing I liked about 2 it's that they gave her stronger NTR content than they did in 1.
That's another story entirely.
By the way, there's some sort of swapping game from Waffle coming out in June:
http://www.getchu.com/soft.phtml?id=897570&gc=gc
Here's hoping there's at least some kind of NTR route like in the ANIM swapping games. I don't think Waffle has done any type of NTR other than netori though, so I'm not holding my breath.