I am a guy and I just finished writing a romance novel. I tried to be very true to the genre (no making fun of the genre, nothing overtly sappy or pornographic, etc.). I figure the novel isn't as good as some in the genre, and hopefully better than others. I'm just now starting to do my research on agents that handle romance.
In your opinion, will being a guy shut me out of the genre, give me an edge as a curiosity, or not make any material difference?
The only thing that matters is how well you write. There are many romance novelists who are of the male persuasion. They can't help it; they were born that way, poor dears. Their novels may come etched in pink and have decidedly un-masculine noms de guerre, but that was a discussion by the marketing department. Here at Snark Central we think pink is the correct color for tough-talking, tammed forces of nature anyway.