Her handlers consider the performance a grand slam home run. EVERYONE in the country is talking about her. There is much back slapping and high firing going on.
In fact that performance probably added $100 million to the bottom line of Miley Inc.
Tough to say. Everyone was talking about Tom Cruise jumping on the couch also, but not sure it helped his career.
However, 99% of the talk I've seen is um "unflattering" at best. This is the kind of thing that in 2 or 3 days everyone will forget because everyone wants to forget it - it is embarrassing for Miley. It should be a career-killer for her choreographer.
In a few weeks if someone says "Miley..." the response will be something along the likes of "Who? ... Oh yeah, that chick that did the stupid and horribly bad act at the VMAs."