As far as I know, this is legit.
The good news first. Chao and Setsuna look perfect, which is great because Setsuna's my favourite character. (Love the expression.) The costuming department also did a good job making Chisame actually resemble the dorky-looking reject she's supposed to be, something that neither !, !? nor Akamatsu-sensei did with any respectability. And Sayo seems to have her character down perfectly, giving an expression that could easily be mistaken for fearsome but, when you think about it, is actually full of harmless cuteness. Kazumi also has her character down, even though her hair is a disaster. Mana looks like the twins that were in my grade 9 before transferring out.
There were some I didn't like, though, which is to be expected with 31 girls hanging around. First of all, KUU FEI. She doesn't look childish or energetic. In fact, she looks like a man! I will not get used to her as long as I live. The other problems I have pale in comparison to her, which is a good thing. Makie, though, comes close; she looks like she has to go to the bathroom, and she's got a bad hair day that cannot be cured. Konoka seems a little plain; maybe I've been seeing her through Setsuna-o-vision so long that I've forgotten what she really looks like, but she just looks boring. Kaede's hair also sucks.
Oh, how could I forget the main characters that matter? Asuna has the quirky-tsundere thing down, but she seems to have gone to Makie's hairstylist, and the ribbons are terrible. Nodoka looks creepy and standoffish, not shy. Wrong character type, people. And why didn't they make Eva a foreigner? Or at that, a loli!? I imagine some serious retconning, or something.
And that concludes What Not to-- er, my very relevant post on the Negima drama cast! Now why don't they reveal the rest of the cast?
This is what Nodoka REALLY looks like, in case you forgot. I'd post a Kuu Fei picture, but the contrast between cute and ugly would fry your brain.