I just turned my portfolio into an 80 page book using Blurb, a print-on-demand publisher.
All told, I think Blurb is a great option for artists who want to make a portfolio. The reaction to a book is always thrilling. "Oh, you have a book..." And with P.O.D it's easy to add new work and then print again.
It took about ten days to assemble all the high-res images and layout the pages. A lot of this time was spent struggling with BookSmart, Blurb's page design software - it crashed regularly, was very slow, and generally was annoying as hell to use.
I went for the largest book size - 13 x 11". At around $70, it comes in at under a dollar a page, which makes it cheaper and more convenient than an inkjet portfolio (around $2 to $4 a print). The book arrived promptly and I was pleased with the results. The image quality was great. There are minor color variations between printings, which irritates me a bit, but I've decided that it irritates me less than spending two days feeding my Epson!
One downside with Blurb is that their paper stock is very susceptible to dings - those little marks and creases that appear where people turn the pages. Art books typically use a heavier paper stock which doesn't kink as easily. Unfortunately Blurb doesn't offer a more durable paper option. I just ordered an extra copy printed for when the first book gets scruffy.
At $70+, the book is an affordable portfolio, but too expensive to just send out as publicity material. For a larger run, I'd need to remaster the design in e.g. InDesign and then find a press in Asia or China that prints at under $15 a copy. Which is a hassle. It would be great if Blurb offered a way to steamline this by partnering with a traditional press, but I don't think this is a priority for them - their main focus is wedding and family albums.