Does the assignment of the favorites icon work differently for different browsers.
I've got one that works fine in Firefox 8, but not in IE 9 (with in private browsing turned on, if that even matters)
Here is the current markup:
<link id="Link1" rel="icon" type="image/png" href="../../App_Themes/STA
o" runat="server" />
should show favorites icon in Mozilla, but not in IE.