I was wondering this same thing. There isn't really a super easy way to detect memory reads, at least without a ton of effort. I HIGHLY doubt the new patch provides this functionality. So given that, just reading from memory and drawing on an external game overlay shouldn't actually be detectable.
edit: just scanned the poehud souce and confirmed that the features that write to memory are: maphack, fullbright, zoomhack, and particle modifications. The loot alert functionality seems to be only reading from memory.
So that means that its probably still safe to use the loot alert portion at least...