Geeksofdoom.com has a piece about the upcoming but very far off development of Mass Effect 4.
We don't know if Shepard will be in it. No, we don't know when it will released. It probably won't be for the Xbox 360 & PS3 but for Next Gen Consoles.Yes, Bioware does want fan input. Why yes, I am that handsome, thank you for noticing.
I hoped I answered all your questions. Here's the link.