I just tried it in Firefox, and it works fine. AFAICT, it's identical to what you see in Chrome... except it has -moz- prefixes everywhere in the CSS. :-p

They use -webkit- to ensure that, when the relevant standards are finalized, the namespace isn't polluted by experimental and development mistakes.

Ever heard of graceful degradation?

Gracefull degradation is for making sites work on older browsers. What about making sites work on modern browsers which are other than your favourite one?

Using just -webkit prefixes everywhere will make sure it just plays nicely with webkit, and not with IE, Opera or Firefox.

It detects your rendering engine when you connect to the server and only serves up the relevent stylesheet. This way you don't get -moz, -o, or IE fixes if you're not on IE, Mozilla, or Opera.

Save bandwidth, load time.