I'm sure this is quite worrying for Sony.
Up to now they have had this particular niche market for themselves; now it seems that Sony's expecting competition soon.
DPReview interviewed Sony's Senior General Manager of the Digital Imaging Business Group, Kenji Tanaka who has this to say;
Q: One of the reasons that companies like Sigma and Tamron are creating native Sony FE lenses is that they’re looking forward to a future where full-frame mirrorless is the norm. How long will that be?
A: This is just my personal opinion, but I think that maybe by next year’s CP+ you’ll see full-frame mirrorless cameras from Canon and Nikon. I think [by then] they will be participating in this market.
Just look at our technologies, like eye focus. All of that data comes from the imaging sensor. In DSLRs, the data comes from separate sensors. The main imaging sensor is blanked out, 90% of the time by the mirror. The sensor is turned off. But the imaging sensor is very important. So if cameras are going to develop, and be more able to capture the moment, manufacturers have to develop mirrorless technologies. So within one year, I think.
If Sony is thinking their own market is going to get more competition it's probably a pretty good indication that both Canon and Nikon have serious development occurring as we speak.
Keep in mind that Canon has most of the pieces now demonstrated to make a fairly serious first version full frame mirrorless.
- The 5D Mark IV sensor is competitive against it's peers and supports over 24 million phase detection points on the sensor.
- DPAF and DIGIC 8 bring quicker AF, wider focus sensitivity which is now down to -2EV, and now supports Eye AF. For the video followers h.264 finally makes it into a camera DIGIC. All of these show up in the entry level EOS M50.
While some questions still linger, how quick can DIGIC 8 run, and also how much support for video will there be, there's good indications that Canon has certainly been working towards a full lineup of mirrorless cameras for a while now.