I got another reply from an agent — this one a rejection notice, but a very interesting one! Here's my reply back, with her original email below that:

It's encouraging that you're representing similar titles! That means it's trending, which is good news for me! Best of luck with them.

At 9:58 AM -0500 6/26/14, Xxxxxx Agency wrote:
Hi Allan,

Thanks for thinking of us!  I'm afraid, however, it is a little too close to something we have forthcoming and potentially forthcoming on our list, so I have to decline. I wish you the very best of luck.

Best,

Xxxxx