My guess the mystery lens will be a 50mm f1.4, this will be a popular focal length in the mass sales market.And theyve said before that they are working on one. Thing is, manual focus 50mm f/1.4 lenses are a dime a dozen out there with adapters, so, Im not sure how successful they'll be with that. Unless its very cheap.
The 10mm lens is one Ive been waiting for a while, price dependent. Looks like its been confirmed: http://www.ukdigital.co.uk/catalogsearch/result/?q=samyang+10mm