Originally Posted by SamL
I get that, but the nook is the only reader I've seen that has that setting at all. And it will still follow the CSS you have in your book in terms of spacing, bold, font-size etc, except for serif/sans-serif aspect.
And margins. Also - if you use a fixed point size, I suspect (though I haven't tried this) that it'll ignore your fonts, and that it only obeys relative sizes without them.
Anyways, I don't know about other hardware readers, but I've seen it in other software ones on iPhone - both RMSDK (Bluefire) and not (Kobo, Stanza). Personally, I think that letting the reader's preferences win is a good thing; book creators don't always know better than me.