Not all books have the same three text sizes. Most BBeB books I've read seem to have larger text sizes than some of the ePUB books, not that you can find many ePUB books in the Sony eBook Store, despite their claim that they would go all ePUB by the EOY.

Don't forget that placing the Reader into landscape increases the font size too. So you actually have six font sizes to choose from--three in portrait view and three in landscape view.

I'm not a fan of the Reader's landscape view because Sony chose to use a faded strip in the page center to show you where you were when you scrolled half a page. It is unnecessary and darn distracting, especially when a page has images. They could easily disable this feature or at least give us the option to disable it.