A quick search of the forums showed that this problem has cropped up for other WordPress users and that it may extend to Safari 2 as well. Here what one user had to say on wordpress.com forums.

This development is personally upsetting to me because I like WordPress, but I love my ancient (2003) iMac G4 running OS-X 10.3.9 Panther with Safari 1.3, better. It is my favoriteest computer ever. I chose not to upgrade it beyond OS-X 10.3.9 (and Safari 1.3) because 10.4 caused this otherwise efficient machine to run sluggishly. This was OK because OSX Panther’s brower, Safari 1.3, worked fine on most sites that I visit…until now, that is.

Although there are alternative browsers like FF and Camino for OS-X 10.3.9 that do work with WordPress 2.6, Safari 1.3 is the preferred browser of many, including myself, because of it’s superior image rendering on the iMac G4. I’d like to be able to keep using it with WordPress.

The source of the WordPress problem is probably a faulty javascript library or library plugin that 2.6 loads, a library/plugin that is so incompatible with Safari 1 that it crashes the browser immediately (like jQuery 1.1.3 did). There may not be a large number of us Safari 1.3 users out there, but there are enough of us to make this problem an important one that needs to be addressed. WordPress developers needs to identify and replace the faulty javascript library/plugin ASAP! Are you paying attention, Matt?