I’ve given up on trying to get a decent book from Blurb; their customer support is unresponsive, so I am left with a book which has posterized images, and is unacceptable.
04-04-2007 emailed blurb about posterization including a link to a flickr set with examples; received an automated reply that I’d get a actual reply within 2 days
04-09-2007 blurb replied that higher DPI was better, and offered $10 off my next purchase; I emailed asking again about the posterization problem.
04-13-2007 blurb replied, asking for photos to see if a reprint was warranted. I replied with photos, and pointed out, again, the link to the flickr set.
04-24-2007 I emailed blurb asking about a reprint.
04-30-2007 Still no reply, so I’ve given up.
Thus, I can only recommend Apple/aperture (and iphoto), and Viovio for high quality books, excellent support, and fabulous prices (at Viovio).