There's a number of Manga that I'm really hoping that they turn into anime. Here's some of them.
Bitter VirginHigh school guy finds out that a girl in his class was abused as a child. In order to get closer to her he has to behave in a non threating and non sexual manner and as he spends time with her realises that he's falling for her but is worried how she'll react if he tries to move from being friends to asking her out.
Chances of a series: pretty low, I mean, who would you market it for. It sure ain't a kids show and it'd be hard to sell it to adults. The Japanese are pretty good at showing their kids that the world isn't all sweetness and light but a high school anime based around a girl recovering from child abuse?! No ball son, move along.
Yakisoba Milk TeaWhen a high school boy is shoved into drag in order to pose for some wedding pictures he finds that he likes cross dressing and embarks on a second life as "Katherine".
Chances of a series: The chances of this one are actually pretty good. Most high-school characters can be voiced by women and at times it's hard to tell the gender of teenage characters at first glance anyway. Take Ouran High School Host Club for an example of this idea in reverse and a precedent for a cross dressing anime. It's more a drama than a comedy but I stil think this one could do quite well.
Lovely ComplexVery tall schoolgirl meets very short school boy and wacky maybe/maybe-not romance ensues.
Chances of a series: They've gone and made it into an anime allready. yay!
(The odd thing is that "tall girl" Risa is said to be 170cm (about 5'7") tall which is a bit shorter than the female average in England. Just goe's to show that even with a changed diet and an increase in average height since WWII the Japanese are still a short race. Wee even.)
OthelloIntroverted high school girl (Yaya) develops a second personality (Nana) in order to deal with high school bullies. The problem is that this new personality likes to start as many problems as she solves and also takes a liking to the boy that Yaya likes and can, and will, be more forceful in taking what she wants than Yaya ever could.
Chances of a series: If they can make Peach girl then by god they can make this. I can see how many studios could shy away from it as using one character design and voice actress to essentially present two distinctly different characters (think Lucy/Nyu in Elfen Lied) can be quite tough. On top of this you'd need to create a whole bunch or really ripping songs for the in-show bands to play (think Beck) and well animated musical instruments and performances (Beck, Haruhi, Nodame) and you'd also need your lead actress to be a damn good singer (ala' Aya Hirano or Megumi Hayashibara) rather than just getting a shitty singer to play the lead and then just have all that other characters go "wow, aren't they great" when it's damn obvious that that aint. Koyuki from Beck, I'm pointing at you here!!
The rest of Yankumi, sorry... GokusenChances of a series: Sorry, this one's fallen into GTO territory

The chances of them finishing this one off is prettttty slim which is a crying shame as the manga's really hotting up.
Manga that i wish they hadn't
Karin. Winner-kun... need I say more?
There's loads more but that's about all I can think off from the top of my head.