favicons cache differently. You either need to enter a different favicon address (favicon.ico?v=2) or reload and restart the browser.

I know it's weird, but favicons are weird.

But it's just an image right? Does the browser decide to treat the image different because of the format or the extension? I'm pretty sure you can use png files as favicons if you want.

Anyways I tried it in IE, including restarting it and it still showed the old lowercase g.