First off the whole Billie turns into a Super Hero deal wasn't really necessary. I've always liked the sub-plots better than the main ones. It was ok, even if it seemed a bit filler.
Now I would like to tal about Bille. I kinda liked her for the first four episodes, but she really has started to get on my nerves, and it was in this episode it finally struck me what a pain in the ass she is. She's an irresponsible brat with no scense of what is inappropriate, Kaley Couco is a BAD actress and god how I hate they way they do her make-up. I was totally grossed out by her lip gloss in The Lost Picture Show. On top of that, I don't think she fills any purpose in the story whatsoever. The sisters don't need her anymore, they're back in full Charmed Mode, and so much stronger than her. I really hope the writers give her something more to act upon. Besides her fondness for demon hunting and the fact that her sister was kidnapped by an unknown demon, we don't know anything about her. But I'm keeping my hopes up. Maybe she'll develope into a good person. It could happen. And it totally drives me nuts that she probably is the reason why Brian has to leave. I think that every Charmed fan would choose Leo over Billie in a second.
It's nice to see that Piper and Leo has got some of their spark back, especially after last week's fights and unagreement from their sides. Theirs often the best parts in the show nowadays, and I never seem to get surprise how well the act together. I really hope they wont break up again, now that Leo's departure is so close.
Paige's sub-plot was probabaly the best one in the episode. She hasn't given up on her life as a whitelighter and some of her dedication and stubborness, which is her most charactersitic qualities, are back. All three of the sisters ahve been a bit off the track since the whole glamoured-identities thing, and I think paige has finally found her path again.
The ending at P3 was ok too. Paige isn't the only one that's up and about again. We haven't seen the club in a long while and it's good that there still are places to count on. The episode also contained some Sister/Bille bonding and they seem to get closer, which is essential when it comes to demon-fighting, and saving the world.
All in all it was a good episode even in it's filler-ness. The standard of this season is really very high, and I hope it won't quit now.