I made my first book recently. Somebody looked at one of my blog posts and requested the photos to be produced in book format.
So, I made one. It's really very nice, though production is not cheap, to say the least. It's a very thin tome and the amount it cost meant that I was only making the barest of profits on it. Self publishing is not a way to make money in photography: a photographer who I like very much self published a book on the north east coast recently, and when ordering it via blurb.com he makes precisely 1p profit (that is, one penny) on each sold. If he charged any more, probably nobody would buy it..
It's great to see my photos in a book, and it's something I'd like to do again in the future, though I'm not sure there's a great deal of commercial viability with the costs as they are, sadly. Blurb are very easy to use however, so anybody thinking of making a book for themselves could certainly do worse, and the quality is excellent.