I like this app as a reader, and the fact that the docs are synced between my MacBook, iPad and iPhone. Also, to write notes and make excel sheets.
There is only 1 thing I miss. When I use it to read large PDF documents I would love to see a bookmark function. That saves me a lot of time, browsing through 1000 pages of some of the PDF-books. Maybe in a version update? [ hint to the author ;-) ]
I know that the iBook app by Apple can do this sort of things. But some docs are too large to mail it to myself, since that seems the only way of adding docs to Apple's iBook app.
Maybe "Documents 3" will be able to help us out :-)