As D3 goes, particularly the real world cash auction house, I've no idea if it's been a "success". Tho i surely wouldnt call it a failure.
Nine year low stockprice? /shrug
As a customer of theirs, i can't explain that since they've been putting out the product, getting their subs, and been offering a variety of merchandise (digital and otherwise). They're workin on a new IP which should help.
My sarcasm would suggest "some moron at Blizz is ruining a good thing". /shrug