I'm thinking it has to do with ebay's choice of layout - putting descriptions in iframes. Some browsers don't support iframes, some security products block them, some anti-advertising stuff blocks them also. I've checked with multiple versions of firefox and seamonkey - no problems for me.
When you guys mention you're having a problem and using 'some browser' your browser or emailing ebay saying it doesn't work, please include the version number with your browser info. You can usually find that under the "help" menu item - about some-browser-program-name.
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