I've tried one. Just so you know, I work in IT, where tech moves on all the time.
Marc says they aren't intended to replace our Swiss mechanicals, however I wouldn't imagine Apple would do it, unless they thought it WILL replace them. They love cornering markets. They've killed off basic digital cameras, many apps have killed off various products etc. I'd be surprised if Apple aren't deluded enough to think they can own the watch market as well; hence the development of the advanced strap system and the gold models etc.