I finished the second season the other day. It's definitely shoujo-ai and not yuri.
One thing I've disliked about all of the shoujo-ai I've seen is that the relationships aren't taken in a serious and realistic manner. Maria-sama ga Miteru mostly sidesteps the issue by taking place in this all-girl's school. The girl's aren't dating, it's a construction of this unique senpai relationship. Yet all the girls have some homosexual lean, the relationships transgress usually accepted bounds of friendship. But they sit in this gray area, carved out by the accepted notion that girls can be more affectionate with each other. There is kissing, though very little and it never goes beyond. Men are almost entirely out of the picture- you'd think one of these girls would pick up a boyfriend. Love is sisterly, not sexual. It's pseudo-gay.
Of course the creators play with the audience, there are several scenes in bed rooms and empty houses that cut at the opportune moment to make you wonder. There are several scenes where you swear two characters are about to kiss but don't. Biggest offender is the last episode of season two, it's disconcerting how blatant it is.
Maria-sama ga Miteru is what it is, and it does it well. I just wish there were a shoujo-ai that dealt with relationships like, say, KareKano; or taboo relationships like Koi Kaze. These works build upon reality and common experiences so the audience can empathize with the characters. Koi Kaze is especially set up in an argumentative format, slowly and tactfully debunking the most prevalent counter-arguments.
Juxtapose that with something like Candy Boy- often touted as the shiny example of good shoujo-ai. That the girls are twins is so matter-of-fact. It seems more like a coincidence than a source for conflict. Yes, Candy Boy is what it is, and is enjoyable if you can wrench yourself from the reality it so readily disregards. But no question, Candy Boy is yuri (pornographic) because the incestuous and gay relationship only exists to titillate the audience. Nothing would be lost plot-wise if the relationship were heterosexual, nonincestuous.
All of the shoujo-ai I've seen is only enjoyable in a vacuum. Aoi Hana almost gets there, but not quite. You have to forget the reality that being gay has undeniable and unfair consequences.
