Thrawn,
I know - it's really hidden!! There's another way, too - when you're in a book, if you touch the lower left hand corner of the screen (where the battery display is on the progress bar?) a "Book Information" dialogue comes up. (It has a page number for you too, but it's a little buggy. That's how I first found out about the Book Information screen - I wanted an actual page number!)
There's a button THERE that says "Add to Desktop". Voila!
Funny enough, you can also do this with Aldiko, but it's just as hidden. On the phone home screen, you do the long-press like you're adding a Widget, but instead you select "Shortcut". Then you select "Aldiko Premium" (dunno if this works in vanilla Aldiko), and then you get your library to choose a book to add to the desktop.
Why these options aren't integrated more...intuitively...baffles me. It's a HUGE feature for ME!!
And I agree that a "hands rubbing in joy and anticipation of cluttering my phone screen with book covers" is needed here!