If you're using iPhoto to organize your pictures anyway, there's almost nothing easier than making a book with this program. It's extremely user friendly, drag and drop the pictures, press order, you're done.
The hardcover photo books come with a dust jacket, which gives you a little extra space to play on the flaps, but dust jackets can be kind of annoying. Currently in iPhoto, there is no option to print an image directly onto the cover.
There are a limited number of page layouts for the iPhoto books. This can be a good thing or a bad thing. If you're documenting one specific event, it's usually not a problem. There are only so many pictures to go in the book anyway. If you're trying to document a whole time period, like I am in the book above, the lack of templates makes the book a little repetitive.
There is also a soft cover option. This paper is higher quality than a magazine, but a similar idea.
I like to do a smaller size soft cover for specific events (like the girls weekend in the above pictures) and then order one for everyone in attendance.
The smaller soft covers are reasonably priced and make a great memento. Since it's SO easy to do right on my laptop, I can usually churn these out before my guests have even made it to the airport.
iPhoto book CONS: Dust covers only for hardcover books, very few templates or styles to choose from.
iPhoto book PROS: So easy to work with, quality covers and paper.
Blurb books are also of very good quality (and they even let you pick the weight of the paper) but it takes a steeper learning curve to make them look exactly how you want. It's not incredibly difficult, but it's not as easy as the iPhoto books.
Their hardcover books (from a certain size and up) can be made with a dust jacket or with an image wrap, where the image is printed directly onto the cover.
They have tons of photo and text layouts to choose from, which is great if you want something very specific, but can be overwhelming if you just want something simple. They do offer an auto-flow option, where it arranges the photos in the book for you based on date or the order they're already in.
Another amazing bonus of blurb for bloggers: They can make a book of your blog! It automatically flows in your posts and pictures, which is a really great feature.
This baby book made by the guests of my baby shower is an example of the image wrapped cover. I love the way that looks, and I've used it several times since.
Blurb Book CONS: Not super intuitive to use, pricey.
Blurb Book PROS: Tons of photo and text options, Image wrapped cover. Specialty extras such as Blog-to-Book, and the ability to create a book that you then sell through the site.
Do you make photo books? Tell me about the sites you've used for it and why.