Esther's a challenging book...no mention of God, lots about the Jews, characters who aren't quite as straight forward as we'd like. If you're reading Esther out of interest's sake and want to go deeper into the text, or you're teaching on Esther, then this is a worthwhile resource to have.
Karen Jobes doesn't mess about with creating solutions to the puzzles of the text with fanciful notions of piety or simply baddies and goodies. Rather she responsibly handles the text and draws out the various themes running through the book in a very readable way, with the usual series application sections. The introduction is particularly good. But as with any commentary, don't just assume what she says is right - think about it!
Definitely worth having and should prove useful for you.