Sounds like Linux Mint will eventually switch to systemd, but the Linux Mint devs aren't in any rush to do so.
hollowface, that's a smart move on their end, not to be rushed.
Because when version 16, a short term release came out, there were reports of the OS not being secure enough for transactions, and they had some patching to do. Fortunately Linux Mint has a large following, and there were likely some of their most dedicated users helping with this.
From what I've read, this played a huge part with Clem sticking with Ubuntu 14.04 LTS for all of Mint 17 releases. And why not? Ubuntu will offer another LTS in at most a couple of more years, if that long, they have a roadmap just as Microsoft does for Windows releases. I just haven't checked it out lately. Just looked for it, kind of hard to find, though I have seen it a few times.
By then, Linux Mint users will gain some of the things that current Ubuntu users are running now, and those users will have a steady, rather than a 'bleeding edge' type of OS. Though it's likely that many who jumps to the next release, even while in the last stages of Preview, will always want the latest Ubuntu possible. That's the way I was with Mint, after a couple of short releases, I didn't use 14 or 15 at all, but did 16. Mint 17 isn't a whole lot different from 16 in some respects, though there were 'under the hood' enhancements added, such as native SSD support.
I just wouldn't know what to do w/out my Linux Mint, a strong breeze of fresh air after running Windows for a day or two. It's getting time for me to dump some of these installs, half of which are test beds.
Hopefully Systemd will happen with Linux Mint 18, though it'll largely depend on what Ubuntu does.