<p>that's the new shortcut to switch right between tabs in <a href="http://www.apple.com/macosx/features/safari/">safari 1.3</a> that gets installed with <a href="http://www.apple.com/downloads/macosx/apple/macosxcombinedupdate1039.html">mac os x 10.3.9</a>. command shift [ being the shortcut to switch left. it used to be the left and right arrows instead of the curly braces. so all i can imagine is that they're using command shift left/right arrow somewhere else that was conflicting in <a href="http://www.apple.com/macosx/">mac os x 10.4 tiger</a> (that's a mouthful). or they are trying to standardize the shortcut for switching between tabs in apps <a href="http://ranchero.com/netnewswire/">since so</a> <a href="http://www.apple.com/safari/">many</a> <a href="http://www.panic.com/transmit/">apps</a> <a href="http://macromates.com/">are</a> <a href="http://iterm.sourceforge.net/">using</a> <a href="http://www.adiumx.com/">them</a> <a href="http://www.omnigroup.com/applications/omniweb/">these</a> <a href="http://www.mozilla.org/products/firefox/">days</a>. presumably, they'll changed the <a href="http://developer.apple.com/documentation/UserExperience/Conceptual/OSXHIGuidelines/XHIGIntro/chapter_1_section_1.html">HIG</a> to reflect this, if the latter is the case.</p>