In my impatience, I've started browsing some mirrors, and sure enough, I found an ISO there, up since two days ago:
I found this.
Scrolling down on that page there's a file named "linuxmint-201403-[DE]-dvd-[number]bit-rc.iso"
Wait, 03? Wasn't it going to be 02? Pushing for an announcement in march? Huh.
Is this the same ISO that's been tested on the community website?