Is the use of relative values in font sizing for accessibility still useful in general, or only for IE6?

Question

All other browsers (not IE6) are scaling the size of the whole layout in px. So what's the purpose to use em and % if we are not thinking about IE6?

Answer 1

Have you considered all major mobile device (eg, phone) browsers as well?

Answer 2

If you specify font sizes by em, your codes will be more flexible and easier to maintain when you want to change the underlying font size later. Also, as Dan McG has said, not all browsers scale in pixels.