Personally, I've been envisioning a system like this since 1999 flying Red Baron. Monitor stays in front of your face, no scaling like Track IR, the next best thing to being there. I've even been tracking head-mounted displays for ten years or so, hoping to find one of sufficient quality that I could afford without winning the lottery. I'm very excited that someone's finally making it happen, and even moreso that it could be reasonably priced.
Able to see the keyboard? Certainly a valid concern. OTOH, this is a WWI sim we're talking about here. It's not like you have flaps or in-flight trim or landing gear to control. I would think that the essentials could be assigned to joystick buttons. But it would be nice if there will be some sort of provision for this. A compromise between immersion and functionality...maybe a switchable window. Ultimately a glove that would allow your hand to interface with the ingame world, but that would definitely require the game's software to be modified.
Resolution? The first generation prototypes are going to be proof-of-concept, so there's no point sinking a lot of R&D money into a highend screen. The second generation (where we are now, my guess) is shake-out-the-bugs, still not critical to go too wild. I can't imagine anyone releasing a gaming monitor these days that is less than 1080 (D3vil says 1440)...and 1080 is plenty good enough to see a one-pixel dot representing an aircraft a few miles distant. It's a question of how much of your field of view that pixel commands. I currently use a 32" 1080 TV for flying and I can't remember the last time anyone snuck up on me when I was scanning properly. I daresay a 7" or 8" screen at 1" from my eyes should take up a greater field of view than one 32" at a foot to a foot-and-a-half. And the thought of UltraHD resolutions makes my mouth water.
I have two concerns: compatibility and the framerate issue raised by CCIP. I may have misunderstood but the impression I got was that this would not be, strictly speaking, plug-and-play...that the game would have to be made compatible with the system. If that's the case, I hope the devs will make the effort. If I'm wrong, so much the better. As for needing to have a steady 60+ fps, well I was thinking about upgrading my video card anyway. This just gives me a good excuse.
Sign m up!!