From The Bookseller:
Last year saw the largest number of titles published since records began 15 years ago, Nielsen Book figures have shown.The UK publishing industry produced more than 133,000 titles during 2009 – an increase of 3.2% on the previous 12 months – hitting the highest output for a single year ever.
When Nielsen first began collating the data, the UK produced fewer than 100,000 titles a year. The highest until now had been 14 shy of 130,000, a figure reached in 2003.
Nielsen said: “The increases can be accounted for in part by growth in print-on-demand (POD) and digital product, which we expect to continue to increase in the future.”
English-language titles recorded by Nielsen Book as having been published somewhere in the world, excluding UK and Ireland, have also grown exponentially, with 2009 showing a record 604,768 publications.
The new book production figures have also increased the overall number of bibliographic records held on the Nielsen Book database to 10.4m globally and 5.8m for UK & Ireland.
Golly. [AR]

I’m not sure why you’re surprised. You wrote most of them. [DR]
That’s my whole point! I only wrote 127,450 books last year. Who wrote all the rest?