Rated 4 out of 5 stars
I have few suggestions of making it even better =)
1 - mark dog-ears with sone smart image, not with dull digits... especially because re-numeration of dog ears is not supported when I somу of them are deleted, and it makes a mess.
2 - make the dog ear icon in status bar sensitive to dog ears at current page. for examle, icon is colored if there is at least one dog ear at the page, and grey, if there is not.