I'm also having a problem with this, and am pretty familiar with WordPress, having installed many versions on many different sites in the past.
-I'm using WP 2.4.8,
-My wp-content folder has permissions set to 777,
-My uploads folder is set to 'wp-content/uploads' in the Miscellaneous settings section,
-'Organize my uploads into month - and year- based folders' is checked.
Normally when I upload an image, it says 'crunching' for a moment, then the image thumbnail is displayed, with all the alignment/title/caption/insert into post options.
In this case, it just shows the image filename, no thumbnail, and a 'show' link that doesn't work.
In the 'Gallery' or 'Media Library' tabs at the top, it's the same thing: no tiny thumbnail on the left, and a 'show' link that doesn't work.
However, coming out of there completely and looking in the 'media' tab on the main WordPress leftnav, there's my image. I can click on it and see a medium sized version, click on that and get the full sized one.
Going back to my page to try and insert that image from the page gallery or the media library still doesn't work.
Here's a possible clue though:
I have only uploaded an image into this install of WP today (Oct 1st) for the first time.
Looking via ftp into wpcontent/uploads/2009/
there are 2 folders: /09 and /10
The /09 folder contains my uploaded image (plus the scaled versions of 150x150 and 300x102 that wordpress creates when uploading).
The /10 folder contains nothing.
I checked my timezone settings and they are set to UTC+1 (Correct for London UK, no?)
Not sure what else to check..
Can anyone offer any further suggestions?
Thanks in advance