SmarTrip vs. Octopus

I've just purchased my first SmarTrip card for the DC Metro. I'm psyched. Never lived anywhere long enough to justify semi-permanent travel paraphenalia!

I thought of the Octopus card which I saw being used in Hong Kong. I got the impression that Hong Kong was, like, so advanced, and stuff, or something, just because they were an Asian country and I saw evidence of a smart-card-type system. So, SmarTrip is a bit of a reality check for me - or was, until I read what the Octopus card is really all about. I guess it can be and is used for anything and everything in HK. Nice.

p.s. Mad props to Wikipedia. Been seeing a lot of it lately. It's like the Google of definitions.