Hi! This is probably a silly question, but what exactly is a flush mount album? Maybe somebody has a picture or a diagram of some sort? Also, maybe there's a good overview of different photo mounting technologies around?
In a flush mount album, the photos are mounted flush with the page—basically because they are the page.
They don't stick up, there are no photo corners, there are no sleeves, they're not tipped in.
In the past the pages would literally be single photos cut to size and mounted. Today it's the same idea, but you can also do fancy layouts thanks to Photoshop and digital exposure units.
Your other big options are traditional albums (smaller-than-page photos are somehow mounted atop a page and stick up), and newfangled "book" albums (glossy book/magazine stock run through a digital printing press and assembled into a book).