What are the details of “Objective-C Literals” mentioned in the Xcode 4.4 release notes?

I was going through the release notes for Xcode 4.4 and noticed this: LLVM 4.0 Compiler Xcode now includes the Apple LLVM Compiler version 4.0, including the following newObjective-C language features: […] – Objective-C literals: create literals for NSArray, NSDictionary, and NSNumber, just the same as the literals for NSString I’m intrigued about this feature. … Read more