A few of you using the Firefox browser let us know right away that our permalinks weren't working right after the Search Engine Watch Blog launched. We fixed that within hours. However, I've been meaning to post exactly what happened, in case others encounter a similar problem.
Each of our posts uses the file format of two-digit year, two-digit month, two-digit day, a dash, then the entry number. Why? It makes it easy for me to know when exactly a post was created. Each post also lacks a file extension. They don't end in .html, .htm, .asp and so on. Why? There's no reason to have a file extension.
One glitch did come up with that, however. Not having an extension meant that our server sent the file to browsers as a "text/plain" MIME type. Internet Explorer, seeing that this supposed "text" file contained HTML, decided to assume the file was in HTML despite what the server was saying. That means IE users had no problems. But Firefox, actually doing exactly what the server instructed, showed the plain text of the file -- causing Firefox users to see the HTML source code.
The solution was easy. The default MIME type for content in our blog area was set to be "text/HTML," solving the Firefox problem.