I always found Dropbox invasive, anyway
This just seems like the next logical step, which I would expect from them.
I haven't used them in years. Can't use it at work -- IT dept won't allow it -- and the integration on my home machine was irritating.
Sure, there are risks involved, but for those who use Dropbox to begin with, blurring the lines between systems is nothing new. Worth the risk to many. And they'll just suss out the fixes as problems arise.
Just like all the other SW that's wedged in there nice 'n' tight.