A while back Mesanna said(in person) that they've written some new code to detect programs being used for things like filling bods, gathering resources and dealing with NPCs so it's not going to be about having two or more accounts online, it's about what any account is actually doing.
That warning on UO.com today also said there would be NO warnings, which is a step harsher than the original(warning paid accounts once). So, if they are finally just going to detect programs it's safe to assume that if you use them and they aren't on the upcoming approved list you are not likely to be safe.
Let me ask you this - Do you believe for ONE SECOND that people with 40 accounts and multiple castles full of bods and more ingots/bods mined per day than is even physically possible without scripts are "legit" as they ALWAYS claim they are? In my experience those who demand the most admiration or flaunt the most wealth tend to be the dirtiest of the dirty.
On the bright side, I suspect we'll be seeing some ownership change in Luna as bans go out. It's equally improbable that vendors constantly stocked 24/7 with one or more 5.0's of every skill type are actually, you know, not bot farming pinks. Same with legendaries, you don't get 100's of them per day by playing normally, lol.
I hope an EM makes an example of one of these multiboxing fools in front of everyone else too btw, there will be no sorrow felt for those people... they've charged 300 million for a 2 minute old rare long enough, lol.
edit: NO GM INTERACTION REQUIRED - so don't go writing gm script halting detection into your code, they won't need to say hello to know if an actual player is there, and it's about time. I hope she's merciless with this, some have become too fat and rich from their scripts.