If they have they are keeping it pretty quiet! My guess is they really dont take Sony as serious competition. Especially given their past attempts to steal market with features like in body stabilization. I really want to like the NEXs but I keep getting turned off by all the little flaws, menus, firmware bugs etc...
There has been a lot of noise about the NEX-7 - and early indications are that the hype is well-founded. What Sony needs to get right still is the lens selection - which is too small at the moment. - The lack of a broad selection is probably the biggest weakness. I also don't like the fact that Sony still does not move to an ISO hotshoe.
That said, there have been a lot of rumours about the upcoming Fuji LX10, and even Leica has a mirrorless system coming - supposedly to be announced at Photokina next year.
If Canon does enter the mirrorless market, hopefully it will be an APS-C offering.
I will be waiting in the wings for now, but will be watching what Fuji announces.
With the advent of decent mobile phone cameras, my compact camera no longer needs to be pocketable. I will probably move mirrorless when it comes time to replace my G11. If Sony can add more lenses, or if Fuji has a solid offering with the rumoured LX10, I may be making a foray away from Canon.