I have a draft with very basic content, a few lines of text plus links. I am unable to paste that in VE (tried it in Chrome and Opera, private and public wikis alike): nothing happens after I do so, sometimes the Save button will be disabled, sometimes I won't be able to say because I didn't add anything to the page. Copy/pasting such content on, say, Gdocs, copying it again and pasting it in VE doesn't make a difference (assuming doing this made sense at all).
If you're interested in digging into this, let me know, I can forward you this mail- it was meant for internal consumption, so this is all I can do.