She has changed labels...This is a greatest hits being released off that label she just separated from. They own the songs and I doubt Amerie would have any say in it. Just another move for the label to make some extra cash off of her.
Of course she wouldn't put "Greatest Hits" in the title, that would be a public embarrassment. But what's the point of a compilation album when she has like 5 singles for her entire career and only ONE of them is recognizable/memorable?