The galleries and individual images (using the image info link) from those galleries don't appear in either Firefox or Safari. I am able to them using IE8 and Opera 11.00.

Try posting at the Web Development / Standards Evangelism forum at MozillaZine. The helpers over there are more knowledgeable about web page development issues with Firefox.
http://forums.mozillazine.org/viewforum.php?f=25
You'll need to register and login to be able to post in that forum.

No problems here on Linux with the images.

See:

• http://kb.mozillazine.org/Images_or_animations_do_not_load
• Fix problems that cause images to not show

• You can see the permissions for the domain in the current tab in Tools > Page Info > Permissions
• You can see all exceptions in Tools > Options > Content: Load Images > Exceptions

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the add-ons is causing the problem (switch to the DEFAULT theme: Tools > Add-ons > Themes).

• Don't make any changes on the Safe mode start window.

See:

• Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems
• Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems

If it does work in Safe-mode then disable all extensions and then try to find which is causing it by enabling one at a time until the problem reappears.

• Use "Disable all add-ons" on the Safe mode start window to disable all extensions.
• Close and restart Firefox after each change via "File > Exit" (Mac: "Firefox > Quit"; Linux: "File > Quit")