I have been tweaking the design on Indiefy lately and I’ve noticed some rendering issues in Internet Explorer.
Originally the layout images for Indiefy were PNG files since I thought that was the best way to go and probably still is if it weren’t for IE screwing with me. IE seems to render certain colors in PNG images darker than they are supposed to be.
The image below is a screenshot of the bottom corner of Indiefy. You have to look kind of hard, but you can see that the IE version makes the border gradient darker than the background color of the page so the gradient does not smooth out. I have not tested this in IE7, but I don’t have much faith that it will be fixed.

So Internet Explorer and PNGs do not get along. There is also the famous issue of IE not supporting alpha transparency in PNGs. Fixing that would make designer’s lives so much easier. Oh well, no one said this would be easy.