I think Shutterfly provides the best quality product of all the on-line photo sites for creating books, cards and other gifts.
I think that Blurb is a fabulous, versatile program that it good for both the novice who wants to use simple templates and the pro who wants to design their books totally free-form. It is free and you can use it on Macs or PCs.
Once you have a very large library of photos, you should probably invest $80 in Aperture. It has professional level photo editing capabilities and unlimited options when it comes to making books, but more importantly has an incredible library management system.
Although I have both PCs and MACs, I do most of my photo work in a MAC framework as I find it so much easier. I grew up with iPhoto and no matter what version you are one, it is rather intuitive and enables you to edit your photos throughout the workflow of creating a book or card.