Spot the diff indeed
Bailz writes:
Click the image for a more readable version. It’s PNG, so if you’re using one of those non-IE browsers … well you might be in trouble…
Graham writes:
PNG is nicer, but unfortunately every moron’s browser of choice botches up the doovy alpha transparencies, so there’s not much incentive to use them.
Hmm…

PNG w/ transparencies works fine for me with IE6
I know one of the other ones doesn’t like it very much either.
Straight (GIF-style) transparencies work fine in IE6/Win.
Alpha transparencies don’t.
(Unfortunately, I don’t know enough about graphics to say exactly what alpha transparencies *are*, only that I’ve seen examples that work in IE5/Mac, Opera, and Mozilla, but none of them work in IE6/Win, and there’s a movement online to get MS to get off their arse about it.)