I put a request in mantis http://mantis.linuxmce.org/view.php?id=3822
when we discussed it last, but there has not been any progress.
I had a pretty reliable setup using 704, where I could press the power button to have the MD suspend to ram and press it again to resume again. It took only a few seconds to resume it. Nice
I just upgraded to 710, so I haven't had the time to set it up again, but it is high on my to do list. I will of course update the wiki article with my new findings, if any, for 710.
Since it seems the release is pretty close, I wouldn't bet on it being included, but I guess some of the devs should answer that. There still is the issue with LMCE loosing state or whatever as you mention. I have not looked into that.
As Ender points out in the mantis log, the suspend may not work with all hardware, so I suggest that there should be a checkbox or something in the pluto admin screen to enable suspend on a per MD basis.