The other day, BiCommunity News tweeted a link to a year old article about Santana's sexuality in Glee.
The gist of the article is that the writer is disappointed that Santana was getting labelled as a lesbian and not a bisexual because of her history with boys. A choice paragraph is as follows:
Even clueless Brittany tries to help Santana’s self-identify by making her a T-shirt that says “Lebanese” (oh how I want one of those, early birthday present anyone?). Now hang on one cotton-picking minute. It’s not the first or the last time that someone in the show alludes to Santana being a lesbian, but everything Santana has done and said so far screams bisexual. A bisexual girl who doesn’t like labels (welcome to the club), and is firmly in a closet, but most definitely bisexual.