Padraic Brady recently made a post about the some of the "deception" that various publishing companies (he specifically mentions Wrox) have made when it comes to publishing books on PHP6. In his latest post he shares a response Wrox made to some of his comments.

In "The Art Of Deception Or Publishing PHP6 Books" I aired my unflattering opinions about publishers who have been selling "PHP 6" books. PHP 6, last I checked, was a bit like Leprechauns. [...] It's certainly not complete and stable, and its future feature list remains a bit flexible. You could see PHP 5.4 in 2011 before PHP 6 is finished...guessing here. As its developers would say - it'll be ready when it's ready. One day. Maybe.

He shares their response to his comments by looking at easy of the books covering PHP6 and two things they're doing to help the situation - pulling the Beginner book and a call for those wanting to make the books better to get involved.