MacBook with Intel GMA 950 graphics:

Coverflow on MacBook

iBook with ATI Radeon 9550 graphics:

Coverflow on iBook

MacBook Pro with ATI Radeon X1600 graphics:

Coverflow on MacBook Pro

For grins, Dell Latitude, Windows XP Pro, Quadro NVS 120M graphics:

Coverflow on Windows

Note that in Windows they don’t even bother to antialias the text, which is in the “wrong” font compared to Mac (here’s the iMac shot again:)

Coverflow on iMac

I’ve also seen this problem in OmniWeb’s Downloads window when using Exposé, but I resized the window and it went away (how’s that for an edge case), and I can’t find the precise window sizing that makes Exposé scale it just right (or wrong, depending on your point of view).

OmniWeb Antialiasing Bug

Thanks & greets to Andrew and Engimo for their screenshots.