Wasn't it not too long ago Steve Jobs did the same thing on a stage for Snow Leopard (or just Leopard, can't remember), comparing it to Vista? This was months before it shipped.
But it actually shipped. And in months, not years. Plus what they demo tends to match what they ship.
Whereas designers like me drooled over the demo videos of the Microsoft Courier dual screen tablet for what, a year? And it ended up never getting made. Drooled over the Crunchpad too and we all know how that went.
Their constant battle with vaporware of various stripes isn't with only one company - some of the competitors ship but slip way behind on dates and/or release hurried crappy releases, some don't ship at all and make true vaporware demos, but Apple tends to rarely pre-announce things and therefore doesn't ever slip behind publicly committed ship dates. Or ship stuff that's clearly beta because of a publicly committed ship date.
Check out how Google hedged their bets by fudging the UI of Google TV. Who knows how this thing will actually work like because the interface in the video was drawn with frigging crayons.
