Just... wow.
And all this in the middle of The Great Recession no less.
Although I guess it shouldn't be a total surprise. I've been an Apple customer since the mid-90's. Right now I have an iPhone 4, an iPad, and an iMac (Summer 2010) and all I can say is damn, these are some very nice machines!
What I love is that despite all the rhetoric you read on web forums, etc. at the end of the day, customers will vote with their wallets. Apple puts out great products that are priced competitively (notice that the competition isn't trying to undercut the iPad's price), with smart marketing that gets the message out.
People can argue this all they want but at the end of the day, the proof is in the numbers. Until competitors can put together a product that delivers a better experience or a demonstrably better value for their money, customers will keep buying Apple.