After upgrade my System from 10.7.5 to 10.8.2 Safari do not show webpages.
Safari 6.0.2 load the code but do now show the page.
Same Page in Readermode is viewable.
It's strange behavior.
From the Safari menu bar, select
Safari ▹ Preferences ▹ Extensions
If any extensions are installed, disable them and test.
Retrieving data ...