Just got back from it now. I'm a huge Gemma fan, so I've been looking foward to this for awhile. And during the wait, I also read the graphic novel (which I loved!) So I had quite high expectations for it...
I have to say, I really enjoyed it. Yes, its a bit of a cluster, and I do agree about the writers not deciding on who is the main character. I would have prefered it to focus on Tamara more, maybe some SATC style narration even. I loved Tamsin Greig and the two tweens were brilliant.
Overall, its a nice adaption, but dosn't work 100%... I wasn't disapointed though, and lots of Gemma... so thats good!
I'd give it 8/10!