After years in the C++ swamp, programming Lua feels like being a world-class sprinter. Sure, there are places where it could be less verbose (the 'function' keyword, if-then-end), but overall it's liberating to have so much power with so little typing.
Ok, it's a visceral (not technical) impression, but there's plenty of places to read about Lua online. I highly recommend giving it a try.
Agreed. It's not as terse as something like Python, but it's pretty speedy and generally a pleasure to program in. (I'd get headaches if I had to look at Objective C blocks all day.) On the other hand, the availability of pure Lua libraries and even the official documentation aren't as complete as they could be.