In his editorial for the Nov. 2008 New York Review of Science Fiction, David G. Hartwell states that they are 20 subscribers in the hole. In over two decades of publishing the nonfiction journal, Hartwell and the other editors have never printed an issue without having the money in the bank to cover the printing costs. But because their margins are so tight, the recent loss of 40 subscribers--a loss due, no doubt, to the economic downturn--means they are facing the real possibility of delaying an issue or two this winter.
I highly recommend this journal to anyone who loves great essays about SF/F. I've been a subscriber for two years and I urge people to consider picking up their own subscription. The NYRSF only needs 20 subscribers to continue their regular publishing schedule. Details on subscribing are on their website.