Jason, in this "women can do anything a man can" world, I still think it's the guy's responsibility to take charge and take the initiative. I think if she's truly your friend and you bring it up in a way that isn't putting her in a huge position, then you can't go wrong.
Saying something like, I'm madly in love with you and can't live without you, is a pretty damn big thing to put on a girl.
Yet, saying something like, I have feelings for you that I need to discuss. Our friendship means the world to me, but I feel like something's telling me we may have something more here. I could be wrong, but I'd like to at least try to see if the chemistry is right and see what happens.
The less pressure the better, but you do want to get your point across. I think women like guys to take the lead (God knows that they end up running the show, but they like to know that at least they can control a man whos got some balls.)
or maybe I'm wrong.