I blew the whole damn thing...
Well, I guess I'm just fueling the fire (no pun intended).
I've had this problem since the day I drove my car off the lot (Dec. 20). I took mine in for service today, although Mazda couldn't replicate the hard start.
While they couldn't replicate, they did load test the battery, sure enough it failed. The replaced, it passed all tests. I drove it off the lot, went 4 miles, car sat 30 minutes, trouble turning over.
I've been using premium since the third tank of gas (was 87 for first, 89 for second, 91/92 on the last two tanks). That could be the culprit by some accounts.
I also have a butt-load of soot/cabon deposit on my exhaust tip.
My "other" thought - this car uses the electronic keychip passive disable system. I don't think that the chip registers in time for the engine to crank, so it just sits there - but that could be a culprit of the battery too.