OK, so there’s a minor flap about the difference between the way Apple software (including when it runs on Windows, now with the new Safari web browser release) renders fonts on-screen, and how Windows does it. You can read a quite nice short discussion of it here: Font smoothing, anti-aliasing, and sub-pixel rendering - Joel on Software
Everyone seems to think that the MS way is more pragmatic in making it readable on screen. Sure, that’s somewhat true most of the time, but there is at least one glaring problem remaining:
What about the descenders?
If you look at the sample given in the article I linked above, look again at the ‘g’s and the ‘y’. I have a real problem the way you just can’t see the descenders when they are underlined. The ‘y’, especially, looks like a ‘v’ to me in the MS version. ‘j’ also looks like ‘i’ in other examples I’ve seen.
To me, that particular issue is a clear DIS-advantage in the on-screen readability of the MS version. So, even if you are not interested in the more subtle things like the unevenness of the kerning, just don’t go thinking that the MS way is always the more readable option, either.
[Update: Contributors on The Joel On Software forum have interesting and informative opinions on this.]