Apple just happened to have caught the entire planet with it's pants down when they introduced the i-Devices. I mean, look at what Google was working on[1] after Apple introduced the original iPhone. Google was chasing the market leader in style and interface at the time (Blackberry). When Apple introduced iPhone 3G, all bets were off and Google went back to the drawing board.
iPod Touch is introduced, and the only real competitor that comes to the fore is Microsoft, with the Zune (RIP) brand that mimics the Touch to no end and barely does anything better (yes, I'm taking the soon-to-be-dead Zune Pass into account).
Now it's tablets, and again, the rest of the industry reacts. I'm certainly surprised MS hasn't tried to hook up with a HW vendor to make a Phone 7 tablet.
Apple is on a hot streak. First with seriously consumer-friendly smartphones, then with software and media ecosystems, now with disruptive computing platforms.
It'll eventually run out of steam, but will the rest of the industry kill itself trying to keep up in the meantime?