Haven't been keeping up with the mirrorless market at all, so accepting the risk of sounding like a complete newb:
Are there any photo blogs of any photographers that is using mirrorless for action/sports?
Not from blogs, but from watching people who attend real events where cameras are accepted and tolerated, there's an interesting pattern.
From a couple of major air shows, a big regional late model stock race, a national amateur road race, several parades and a state championship horse show, the most frequently seen cameras have been on smart phones and tablets.
Then there's a variety of compact digital cameras, followed by DSLR's, usually with an entry-level "kit" lens in the 18-55mm range. In all the events I've attended since th start of spring, I've seen no more than two mirrorless cameras.
Now I don't attend every camera-friendly event in this area and what I notice is no more than anecdotal, but I've seen nothing to indicate there's any substantial move to mirrorless.
I'll wager a guess why that's happening. Switching from one camera type is currently an act of faith, since the number of specialized camera and electronics stores most likely to sell mirrorless cameras has been declining. That's something demonstrated by the number of people who ask about camera capabilities in forums such as this rather than learning first-hand at the sort of brick and mortar stores increasingly held in disdain in an online era.
Just being told a substantial camera purchase is desirable may not be enough to get a person to buy on. More places to actually test and try mirrorless cameras will be needed, along with more aggressive marketing.