lucy24 - 9:11 pm on Mar 7, 2013 (gmt 0)
IE10 doesn't recognize png for favicons
No skin off my nose. Keeping favicons with an extension all their own makes log processing a lot easier; I've had to add whole extra loops just to separate out all those apple-touch-icon permutations* from other png's.
* I think there are eight, but all I can be sure of is that if a UA requests two, it will be two I haven't got. This is the Traffic Light Principle.