Actually, Objective-C as a language/syntax is supported out of the box. What I was hoping to get from the TextMate bundle was the ability to type the first few characters of a selector/method name and tab-complete it or pull up a method list. This is a huge time-saver in both TextMate and Xcode.
I placed the bundle in:
~/Library/Application Support/Sublime Text 2/Packages/Objective-C/
This path was pre-existing and contained two files:
I added a third:
As I mentioned before, a restart didn't result in any of the bundles commands being made available.