WordPress always used to be behind the JQuery curve which gave time for plugins and frameworks to fix bugs before moving ahead but now it's jumped to the latest and many things have broken.
I have a problem with jQuery UI elements which no longer work properly but are fine with jQuery 1.5.2. I have to override the 1.6.1 with a 1.5.2 download which breaks some of the admin UI but the site seems to work fine
Please go back a step with jQuery
Also I hate the font in the admin text input area
You guys need to calm down with updates to the admin. WordPress is about what the user views and breaking sites with fancy admin features is no good to anyone.