Just unveiled last night at Mech Con, and developed by Piranha Games who run Mechwarrior Online.
Clearly lots of work to do, but it is at least being worked on and is due in 2018. I'm a little disappointed that it's being made by PGI, who don't seem to have vast resources (there's been minimal development to MWO this year, nothing but monthly premium mechpack releases and a few changes that much of the community hated), but hey, new single player battlemech combat!
Another thing that concerns me is the setting; 3015. The Clan invasion didn't happen until 3049, so just about every classic mech chassis from Mechwarrior 2 is going to be absent; no Timber Wolf/Mad Cat, Mad Dog/Vulture, Summoner/Thor, Dire Wolf/Daishi etc., unless there's some sort of time skip.