In reply to Jono.r23:
I strongly prefer the 2012 Yorkshire Gritstone Guides (2 volumes, with Trad climbs too). They cover loads of venues, are well made, easy to navigate and the info is good. I'd love to see a single, combined, updated, more definitive bouldering guide produced from this.
I sometimes take out the 2008 Cameron Duff guide. This has drawings rather than photos (which I prefer). I covers limited venues but it has loads more climbs than all of the other guides, so it's great for finding new stuff at venues that I go to a lot (such as Almscliff).
I also have the two Total Climbing Guides. These are ok, especially volume 1, but there a few things I'm not keen on. Printing is poor so detail is lost in some of the photos. There are a few mistakes here and there. The emphasis is often on hard climbing - above my ability.
It's great that we have so much choice