Alas, my comic book/gaming store didn't have this game, so I ended up going the PDF route. On the plus side, I've now read the whole thing cover to cover and can give a more informed opinion.
First of all, given some of the discussion here, I have to say that I see absolutely nothing wrong with making this a girls' game. It's got my daughter sixteen kinds of excited that she's finally got a game to play with her dad. Of course, rules for adding boys to the mix are stated quite simply on page 5 of the text, as well as the options required to make it more like Harry Potter. Boom! Problem (for some) solved. Now, let's get to the game.
I've a veteran gamer. I started with the three books and went from there to just about every game I could get my hands on. I've played vastly complicated rules sets and very simple, from HarnMaster to Over the Edge, and everything in between.
These rules rock. I have no objection to the dice used, because they're really not hard to grasp. My daughter just calls them Dad Dice and her friend, who has never roleplayed before, grasped them instantly. Is reading a number really so hard? I didn't think so, either.
The game also states three times on the first real page of text that this is a work of pure fiction and fun, not a representation of any real world belief system, which I find refreshing. And if some girl goes into a pagan shop looking to duplicate stuff from the game, they can be gently directed into real paganism instead, so the numbers grow. Again, woot for the pagans!
So in reading more deeply, the system is very cool. Easy to grasp, quick to play, and simple to resolve. I can only think that the people who are poo pooing it haven't actually read it. There really isn't anything difficult at all going on here. It's not as simple as Over the Edge (but what is?), but it's certainly far simpler than any of the big name games (D&D, WoD, or GURPS), which makes it a great entry into gaming.
There are lots of juicy options, too, esepecially for a simple system. The Heritages are particularly fun to me, and they and the Talents really help characters end up different from a purely numerical standpoint, especially important in a game where the characters could potentially all be very similar.
Finally, the magic system rocks. I was a tester on just about every one of the 5th edition Ars Magica books, and I like a beefy magic system. WGA's magic system is reminiscent of it in a big way, though much more streamlined at the same time. As such, it gives a huge number of magical options while also being easy to work with, especially if the Director is a long-time gamer.
But the game system is simple, and the setting has a charm to it that Charmed could never have come close to. It's reminiscent of Harry Potter, to be sure, but it's also got a uniquely American feel to it (my daughter has been pouring over the shopping section and drooling fiercely).
Finally, while this game is aimed primarily at girls of roughly the same age as the Stars, I know of a lot of older gamers of both genders who are curious, if not outright interested, in the game. After all, isn't one of the points of roleplaying to be something you aren't?
All of that said, I'm also looking forward to seeing how my own setting (a similar idea in the basic sense, but vastly different in a lot of the particulars) will plug into the system. It looks to be the best fit I've found to date (impressive, given that I've been running my setting for almost a decade and been working on details of it for almost twice that long). A few minor modifications and it should be a go.
So overall, I will have to rate it Darth Vader style, and simply say, "Impressive... Most impressive."