A List Apart’s font switcher is a great explanation of EXACTLY what we went through on B&A. Sometimes B&A’s “large font version” is smaller than the regular version, simply because large font is em’s. and em’s are… well… unpredicatable. EH is in em’s (you’re soaking in it!) but it’s a personal site and I can torture my readers as i see fit. (and you complain with equal joy!)
B&A has certain goals to meet and px were sort of what we got stuck with. (long story. don’t ask)
I pray every night now for the next generation of browsers to use standard code, but hey, what’s the odds of that?
Until then i guess it’s up to us to try to invent things like the “large font version”, IHT’s scalable fonts and so on to try to treat our readers right.
One more thing… several people have written to me to ask why have a “large font version” when I could just use em’s. Well, other than em’s lively behavior, I’ve seen in many many many usability tests (including the ones we just did this week) that the bulk of surfers have no idea how to change their font size. So when they come to a site that is hard to read, they just leave.
So if your audience is not made up of web professionals, consider adding a clearly labeled large font version. If IE and Netscape aren’t going to do the right thing, I suppose it’s up to us.