The Nikon D5100 DSLR is the replacement of the already discontinued D5000 and should be announced in the next 36 hours. Here are the expected D5100 specs:
The official announcement should be on April 4th or 5th, 2011. This means that the Nikon US website will be updated either tonight or Monday night around midnight. I will be online covering the latest news.
I don’t know of any other products to be announced with the D5100. There was some chatter about a Coolpix presentation along side of the D5100 announcement, but I think this will just be a rerun of the latest Coolpix cameras announced in February.
I have not heard anything about Nikon’s mirrorless solution.