Great point Jeanne, Safari (which now also has a Windows version - although it views entirely differently on a Mac, of course...), and Opera are also good points of reference - while Opera doesn't have a huge following it does view differently - drastically in some cases.

Mac, however, always has been, and likely will continue to be, the bane of my existence

The other thing to keep in mind is IE6 and IE7 view differently in some cases too...and people are slow to make the move.

__________________