I seem to be having a problem rendering my blog from StumbleUpon if viewed in Safari 5.0.3 (6533.19.4) or Chrome 7.0.517.44 -- Firefox, for some reason, seems to work. An example URL would be: http://su.pr/2BCLkA
I really have no idea how to debug this and I do not know if it is a Wordpress 3.0.1 issue, an Atahulpa 3.5.3 issue, or something else but I know StumbleUpon -- in general -- seems to work fine with other sites on these browsers outside of my blog. With Safari I see a "Canceled opening the page" comment listed in the status bar on the bottom. If I close the StumbleUpon frame and have it load the site directly it does come up fine.