As I've mentioned before, I've gotten it so that my entire photo workflow is on my iPad... Until the very end. To order prints, I've got to use my desktop. And now that I want photo books for Christmas, same deal.
Now, there aren't zero options. Walgreens has basic print ordering on their app, and a (poorly-designed) app called LifePics allows print ordering to CVS, Ritz Camera, and a few other places. So if you want 4x6, 5x7, or 8x10 prints, and your pictures are already cropped to the right size (these apps won't help you there), there are a couple of options. But seriously, why don't companies like Photobucket and Shutterfly have this option in their apps? Are they allergic to money? As far as I know, Apple only takes a 30% cut on in-app downloads, not physical merchandise.
Same for photo books. They could easily turn the flash book-making services on their sites into apps. The apps would likely be smoother than the sites! But right now, I seem to have two options: use a scrapbooking app like ScrapPad or Album App to design the book, email it to myself, convert to PDF, then use the desktop just to upload the PDFs to a bookmaking site that will take them; OR use a flash browser like Puffin to navigate a slow, half-assed version of their bookmaking sites.
This is the kind of thing the iPad was born to do. Page layout via touch beats via mouse any day (and this is something I've done professionally via mouse and trackball). Whoever realizes this first has a pile of cash waiting for them.