At last I’ve found a good reference on which browsers support which types of icons/png’s etc for the Favicon. I guess the news is that you need more than one approach if you’re wanting to serve a favicon to the most potential users.
browsers
Do Web Sites need to look exactly the same in every browser?
It’s on the internet so it must be right 😉
http://dowebsitesneedtolookexactlythesameineverybrowser.com/
Does that mean I can go home now?
…but seriously, it does make you stop and think a little and get a bit of perspective