(Warning, there be some light spoilers ahead.)
So far... so interesting.
I've never watched an idol anime before, and tuned in partially to see what all the fuss about pantsu was about. Watching the trailers, I didn't see anything to indicate this was "that kind of a show" so I was curious. I watched the first ep, and was confused as to what exactly is going on, but some digging on the 'net lead me to find that the movie isn't optional, it's actually Episode 0. So, I watched the movie and I was hooked.
As I said, I've never watched an idol anime before, but sliding past the half century mark I've seen more than my share of "_____ and tries to make it big" movies. Wake Up, Girls! certainly recycles it's share of tropes from those kinds of movies, but it also adds a few twists of it's own. It's also a bit darker in tone in spots than one might expect of that kind of story. Going forward, the companion stories of the wildy sucessful I-1 club and the struggles of the Wake Up Girls! should provide some interesting comparison and contrast and an opputunity to tell more than one story within the show. It's marked down to seven however because despite some twists and turns, it does drag and it's slow off the mark.
The animation is... not that good. There's nice background details (search around and you'll find videos comparing the anime to real locations in Sendai, they've done well there) but the characters are mostly drawn and animated fairly simply. You can tell the main characters apart, but that's about it. The exceptions... President Tange gets extra detail and attention for some reason, and the dance scenes are well done and very fluid. It's the dance scenes that really pull this up. If you insist on quality animation, this isn't the series for you. If you're willing to overlook some roughness because there's more to anime than that, Wake up, Girls! might be worth checking out.
Nice voice work, especially on the songs, and nice background noises. There's not much more to be said.
Sure, the girls are a something of a collection of tropes but I find them loveable and individual regardless. There's been a bit of spotlighting (understandable in the case of Mayu as her background is important), but overall the girls personalities have generally been allowed to emerge naturally as part of the story. The President is well drawn, and even if her motives were purely predatory in the begining, she's slowly starting to care for the girls and their careers. Manager Matsuda is a bit of a cipher... I hope they do more with him as the series progresses. And then there's the Mysterious Otaku - Mayu's fan/stalker/staunch defender on chans... I have this feeling he's going to be more. I hope he's going to be more (and not a 'bad' kind of more). He's getting an awful lot of screen time for a throwaway.
Rough in spots, decent enough but not great. If you're willing to overlook something of a lack of polish and sophistication, it's worth looking at as it shows potential.
Oh, and the pantsu? Yeah, in episode 1 they're a bit shocking and unexpected. Watch the movie, they make sense in the context there (which doesn't appear in episode 1) and the whole sequence is a setup for a later episode.