First up, we have the SD group announcing at CES that they're coming up with an open standard for wireless transmission from an SD card. This was almost immediately met with a response from EyeFi, which I interpreted as saying "we own the intellectual property on that, back off."
So we probably won't have standards for WiFi-on-a-card any time soon, at least not without litigation involved. I suspect that some camera makers were behind this new standard idea: by putting WiFi on the card instead of the camera it takes the cost of implementation out of the camera itself.
Frankly, I think the right approach is to put WiFi in the camera: first, it reduces potential consumer duplication costs (WiFi in every card you buy), but more importantly communication is something that's more useful if the camera controls it. We need integration of communication, not addition. Of course, the problem is that the camera companies haven't figured out "integration with what and how" despite the obvious answers being right in front of their noses.
Meanwhile, Photography Blog reports that both Lexar and SanDisk have no plans to release XQD cards, at least in the near future. This makes Nikon's decision to go with XQD in the D4 potentially more eyebrow-raising than it at first seemed (which was already eyebrow-raising). What seems a bit strange is that SanDisk was one of the three proposers of the XQD card back in 2010 (Sony and Nikon were the other two).
Technically, the CompactFlash Association is the holder of the XQD specification now, but with SanDisk and Lexar declining to produce cards, at least at the moment it appears that Sony and Nikon are the only real players in this new game. The quote from in Rob Galbraith's interview with Toshiaki Akagi--"we don't know which companies will be making XQD, other than Sony"--is a disturbing one, as it seems to imply that Nikon knew that there was a strong potential for XQD to be single source for awhile. That, of course, has implications on XQD card availability and prices.
Nikon's XQD commitment is feeling a bit like Apple's Thunderbolt decision at the moment: too early. The potential D4 user wanted matching card slots, but with little third-party XQD support early on we effectively got a single CF slot. Yep, another friction for the customer.