As many of you know, I am the webmaster for several JW discussion websites. As a rule, any new site I install and maintain uses Wordpress as it's background operating system.
While working on the new Freeminds.org website, I happened to upgrade to the latest version of Wordpress. (v3.5). I immediately noticed some serious issues.
I was able to work around most of them using plugins or my own ingenuity, but then I noticed a few new issues that I simply could not resolve on my own.
The folks are Wordpress have been swamped with support forum hits from irate users that upgraded and the found their sites were not nearly as functional as before and in some cases (loading and inserting media) were not working at all.
Wordpress 3.4.5 is the last stable version. However, in order to retrograde back to an earlier version from 3.5 you have to use FTP and work directly on the server. You will also lose some functions temporarily and will have to go back in and redo some of your custom programming.
I can recognize that some of the more popular sites are using Wordpress. I suggest that you continue to do so as it is easy to work with and maintain compared to other publishing and blog formats. This does not necessarily apply to sites originating from Wordpress.com (the free hosting site) - only stand alone sites on private servers.
For now DO NOT UPGRADE any of your existing sites to Wordpress 3. 5. If you are in the middle of creating a new site, go slowly and be very careful.
I expect Wordpress to have fixes released within the next few days. They are typically very responsive to user complaints.