font-size: absolute-size keywords vs. pixels

Alright, font-size, what’s the big deal right? We have so many options: keywords like larger and smaller, absolute-size keywords like small, medium, and large, pixels, ex, em, in, cm, mm, pt, pc, etc… Well let’s narrow this down quickly to the two most commonly used: Absolute-size and pixels.
For those who have read Bulletproof Web Design by Dan Cederholm, you’ll know his argument for absolute-size keywords. For those who don’t know, I’ll explain. Pixels work very well in all circumstances except for one: Internet Explorer. Unfortunately in Internet Explorer, when a website uses pixels to define font sizes, users don’t have the option to resize text, making the site less flexible, or less “bulletproof.” For this reason, Cederholm explains that absolute-sizes like small,medium, and large are the way to go.
For quite some time, I tried to stick to this rule while designing with CSS. Recently though, while redesigning Pixelspread, I ran into an issue. Small was too large and xx-small was too small for the size of all my text. It may be a small detail, but when looking at the text relative to all other text on the page, it just wasn’t right.
So how did I solve it? Switch back to pixels! 11px was perfect for the font size. And after switching back to pixels, I could now take advantage of the precision that came with that. I also have the piece of mind knowing that pixels do not change from browser to browser.

So what am I trying to say? Should we not be coding for flexibility? No, not at all. My point is this: As designers, we should try to be progressive. It’s time to find our audience, and stop coding for the slow kid in the back of the class (i.e. Internet Explorer… yes, I totally used i.e. on purpose.) For certain sites, I believe that absolute-size keywords are still going to be the right answer, but every chance we get, we really need to be using CSS as it was meant to be used. Not as Microsoft butchers it.