It depends... according to Friday's (5/13/05) Perl.com newsletter. O'Reilly is releasing Learning Perl, 4th ed. and Advanced Perl Programming, 2nd ed. in June.

Yet those are updates to older editions, not new books (albeit the 2nd Edition of Advanced Perl Programming might as well be new since the first was published in 1997).

I personally own 3 O'Reilly, one Apress, so for me it is still O'Reilly. Yet the best Perl book I own (and am still trying to digest) is Higher Order Perl by Mark Jason Dominus and that is published by Morgan Kaufmann, which I've never heard of before...