Go to any website that has:
<link rel="apple-touch-icon" href="/apple-touch-icon.png" /> <link rel="apple-touch-icon-precomposed" href="/apple-touch-icon.png" />
Create a bookmark from the browsers.
Go to Bookmarks, and Add to Homescreen.
On other Android devices, the icon that appears on your homescreen will be the icon specified in one of the two tags above. On my Nexus 7 though, it always uses a bookmark icon with the site's favicon in the middle. I know the icons are working, because if you go into Chrome => Bookmarks, it shows the bookmarks with the apple-touch-icon there, just not on the homescreen.
Did this change in Jellybean? Is it a bug, or intentional for some reason? I can't find any mention of this behavior anywhere online.