In reply to Rich Kirby:
See, I would disagree. I think that the new BMC guides do surpass the Rockfax and NWR. They are chock full of history, comedy, quirks and interesting mini articles. They are things of beauty. (and they are still voluntary, with the exception of the BMC mastermind).
It probably doesn't help that I've never been a massive fan of North Wales Rock and don't really think that it lived up to the hype. It's a very competent guidebook, and better than the contemporaneous definitives but doesn't blow my mind. I would agree that it gave the CC a kick, and they have again surpassed the professionals. I am also expecting the new guides to up the ante even further.
Then again, the North Wales bouldering guide was a thing of beauty when it came out, but now looks dated in its use of diagrams rather than photo topos. However, this book certainly has an important place in the progression of guidebook history.