Here’s a tab with a nice transparency:

buzilla.mozilla.org

Here’s one that isn’t transparent:

wordpress.com

Here’s a url bar over http:

yahoo.com

Here’s a url bar over https:

safepasswd.com

Here’s a url bar over https with an EV SSL cert:

ebay.com

Here’s a url bar over https that doesn’t have a transparent favicon:

chase.com

If your a photoshop user and use an ICO favicon, you can use this plugin to generate them on Mac/Win with pretty much any remotely modern version. It’s available under GPL. I recall you can easily do so using GIMP as well, though I’m no GIMP pro, so I’ll leave it to someone else to document the best way to do so. PNG also supports transparency through pretty much any program that can save PNG‘s.

So spread the word. Designers, it’s time to start fixing up those few pixels of whitespace. It would make things look so much better.