I'd love to know more about the seasonality of publishing. Are most acquisitions made at certain times of the year? How short and long can the lead times be, from contract to publishing?
Acquisitions are not seasonal; only publication is. We acquire all year round for all kinds of things. (If you have a Christmas story, though, you might want to avoid sending it in December, January, or February, which is when we get all the Christmas stories. Those months also coincide with most people (and editors are no exception) being either overwhelmed with things to do for Christmas, or feeling like they've had enough of Christmas to last them till next December. I got a Christmas story last month, and I think at least part of how pleased I am with it is the fact that it arrived in June.)
The period between contract and publication can be quick (18 months), long (7 years), or even eternal (there's a contract for what? Was that what's-her-face's, who left in '04?).
The 'long' and 'eternal' scenarios are unusual, though, and at least partially the doing of the author, who ought to (a) have an idea of when the publisher means to publish her book and (b) be prodding the publisher regularly when there's no word. Normal scenarios can range from 18 months to 4 years (but only 3 to 4 years if you're waiting for a really great illustrator to have time to put your book in his schedule. The big names are always booked for a couple of years out).
More questions, please.