First, I like to aplologize to anyone who I may have come over too passionate at some times. Frustration is known to get the better of me, even though I should control that. (I also quit smoking.)
Not sure where a new font stack should be discussed, so I'm just throwing it in here. Also, note I propose this for Latin wikis only.
Asuming we want the 'Helvetca' look for the body font:
font-family: "Nimbus Sans L", "Helvetica Neue", Arial, Helvetica, sans-serif;
Breakdown:
Nimbus Sans L - for Linux. This is the defacto helv font on Linux systems which result in an look similair to Mac/Windows. Windows will not match this font, as the Windows versions of the Nimbus font packages have different font family names (ie. 'NimbusSanL' instead of 'Nimbus Sans L').
Helvetica Neue - for Mac. Like Nimbus, this should not match fonts on Windows (or Linux for that matter), as those copies for Windows have differen font family names (like 'Helvetica Neue LT Com 55 Roman').
Arial - For Windows. Positioned after Nimbus Sans and Helvetica Neue, so Mac and Linux do not match Arial, but positioned before Helvetica to prevent matching an inferiour Helvetica font that may be installed on some Windows machines.
Helvetica - Generic Helvetica fallback for any system not matching any of the previous fonts.
I'd like to test this locally on the English Wikipedia, and I am quit confident this makes everyone happy because 1) every OS should end up using a native font, and 2) it "promotes" a free font at the beginning of the stack (not a high priority in my book though).
Next up I may think about the headers font stack; While Georgia is a good serif; I detest its use of text figures.
Regards,