I believe it used to show all your images in an easy-to-click kind of way, but mine just shows an empty page with a text field and an 'Insert' button.
Windows 7 64-bit
Google Chrome 5.0.375.125
No plugins enabled
The page it opens in the pop-up window is:
http://wow.allakhazam.com/cgi-bin/userimages-popup.pl
I'm using the old (classic) World of Warcraft skin.
Do you want a screenshot of it?
Edited, Aug 4th 2010 9:05am by Mazra