One thing that Safari has gotten wrong ever since it debuted is that it applies anti-aliasing to all typefaces, including small monospaced fonts such as 9- and 10-point Monaco.
Yes, yes, the Mac OS X zeitgeist is such that anti-aliasing is everywhere. But small-point monospaced fonts are the exception to the rule, for good reason. Monospaced typefaces are an anachronism, a throw-back to the typewriter era. They are, for most purposes, ugly; their metrics contradict the basic precepts of proper typesetting. With regular (non-monospaced) fonts, small punctuation marks such as commas and apostrophes fit snugly next to adjacent alphabetic characters; punctuation is intended to be subtle. But with a monospaced font, every character consumes the same amount of horizontal space on the line; it’s downright silly that an apostrophe should consume the same space as an “m.”
Downright silly, perhaps, but I find a certain elegance in monospaced fonts. After all, look at my logo and tagline!
I differ with Gruber only in his observation of Geneva in Camino versus Safari: I think Geneva looks better in Safari, though, I admit, at the same point size, it is slightly less readable than in Camino.