Well, got back my photo book, printed through
www.blurb.com, and I must say, I am very very very happy with the quality of the photos. I have at least 10 photos shot at ISO 1600, printed at 12x12 with minimal noise reduction (mainly because I really don't know how to do it properly, yet!), and they look great.
The noise looks really well controlled, not at all distracting, and in some cases, actually add to the intent of the photographs. Granted, these were black and white, but all in all, looks much better than I anticipated, and just goes to show that your computer monitor can sometimes deceive you (must be a resolution thing, or something else I don't understand) into thinking a problem is much worse than it really is (or better in some cases

).
I highly recommend getting some photos together and printing a book (you can get for as low as $50.00, and compared to what you normally spend on photography, that's nothing). It will really, really improve your photography IMO and probably help you to get to that next level.
Best of all, the clients were very happy.