She's actually got a few voice control issues still, which are apparent in this song, but she has most definitely gotten better. Also, practically every artist gets an auto tune on their vocals nowadays. That has been pretty standard procedure in the mixing process for at least a couple of decades. If someone goes to an audio arts university of some kind, they will learn that it's quite normal to use vocal enhancements for the vocalist(s), and auto tuning is a part of vocal enhancement. In the normal case, the auto tuning isn't for stylization, but for stabilization. I can almost guarantee that the song in the OP does have auto tuning, just because of that, not because Rebecca sucks or something. She isn't all that bad, but I'm definitely not a fan anyway, simply because her music isn't very inspired in my eyes. She's taken a lot of crap and hate from people though, so I do feel kinda sorry for her in that regard, and I also have a slight amount of respect for her because of that, because she hasn't really let all the hate stop her and she's seemed to hold up pretty well emotionally (no emotional breakdowns that I've heard of, though I don't follow gossip and crap like that).
In case anyone is wondering, I know all that about auto tuning because I used to have a home recording studio, and I studied a bit of these matters when I was recording/mixing/mastering. I no longer have a complete studio though, because I ran into a tight spot with money and I had to sell most of my equipment, so now I don't do so much of that anymore. Quite a bummer. At least I still have my custom electric guitar and my Breedlove!