I'm not sure it has anything to do with multiminer at all, it seems CGminer is suddenly forgetting my devices. I'm going to give bfgminer a shot and see if I get the same sort of errors. Any input?
EDIT: just to clarify this is an error that appears after the miner has been running a little while. So it does connect to my pools and my GPU and erupters successfully mine for a little bit, then crash.
Your assessment is pretty much dead on. I've seen similar things with cgminer and I've personally had better luck with bfgminer in this regard. MultiMiner is running "cgminer -d?", cgminer is telling MultiMiner there's a device #0 and then, some time later, cgminer is saying there is no longer a device #0.