I just wanted to add to the mix here. I sent a query letter to Launchbooks and received this rejection letter back.
Thanks for contacting me about your work. Unfortunately, I don't think it's quite a fit for me as an agent. However, I would encourage you to contact other agents about your work as often it's just a matter of talking to enough people until you find someone who connects with what you're doing.
And of course, I wish you all the best of success with the book going forward.
Best regards,
--David
it was very friendly, it was positive and it came less than 24 hrs after the query letter. It was nice to hear back from someone in a positive way. One rejection I got was simply "Not for me. - Signed, So n So". or no response at all.
So While I'm bummed the book wasn't for him, at least he did it in a way that didn't make me feel like crap. lol