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The slideshow in Mail
Automator (what I've understood of it)
Spotlight
Dashboard
Dictionary

There are just so many improvement in Tiger but there are my top 5.
 
I like Safari RSS and Widgets. But, I like the Tiger's furture potential more than anything as developers create programs optimized for Tiger's capabilities (CoreImage and all). The new OS comes with a promise or expectation of more new things to come from new or updated software.
 
YS2003 said:
I like Safari RSS and Widgets. But, I like the Tiger's furture potential more than anything as developers create programs optimized for Tiger's capabilities (CoreImage and all). The new OS comes with a promise or expectation of more new things to come from new or updated software.
Don't forget that Tiger also lays the needed groundwork for making Mac OS X truly great in the future while causing minimal disruption to existing programs...that, by itself, is a pretty compelling reason for a developer like me to get Tiger.
 
The new Character Palette. What was great just got even better.
(Bet I'm the only person who says that; most people don't even know it's there, but it's an awesome feature for those studying or trying to translate Kanji.)

Actually, I'd probably say the new 2D graphics engine, since it eliminates all tearing on LCD monitors, but that's more of an improvement than a "new feature". Runners up are the new Dictionary and Dashboard.
 
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