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I would think that more functionality will be added to the Text Substitutions in 10.6.x updates. I haven't had a chance to use it yet, but I can think of lots of ways this will be useful to me.
 
Thought of another one:

gen : generation

Come to think of it... I want text substitutions for the iPhone! I know it already has some substitutions, but we should be able to customize it. I mean, it would be cool if I could turn SL into Snow Leopard just to make it easier to type on the iPhone. Plus, it would be nice for the iPhone to automatically capitalize certain words that I specify such as "Apple" or "Finder". You know?
 
Hmm I thought this was supposed to be universal and on the fly? As well as universal spelling and autocorrect for common mistakes.

Am i missing something?
 
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