Doesn't anyone else think it is odd that while there was a Windows XP Tablet Edition (in 2002 even), and even Vista had an on-screen keyboard, most people say Microsoft was late to the tablet party? I do.
I remember the first tablets coming out, but they were expensive and under-powered. Still, I remember seeing them at the doctor's office and a few other places. A $2500 tablet is inaccessible to most people, Apple got it right with a sub-$1000, heck sub-$600 iPad tablet. It wasn't a full on OS, it was a slightly bigger phone OS, but iPad was what got people into tablets.
Microsoft recently demoed Windows 8 on YouTube: Windows 8 Demo
It looks like a pure tablet OS - except it is a full version of Windows. It will also run on ARM processors, the cheap processors in your cell phone, not the expensive mobile versions of desktop processors that previous Windows tablets used. This means reasonable prices and a desktop caliber OS.
A recent interview with a Microsoft executive showed Microsoft's concern for hitting the market. There was a huge lag between IE6 and IE7, Windows XP and Windows Vista. Microsoft's product cycles are measured in geological time, something unacceptable in a fast moving high-tech world. They're acknowledging it, and moving on it, but its too late - they're already buried.
Apple is clearly dominating the tablet market, and the iPhone is the gold standard for cell phones. Steve Jobs and the Apple team know exactly how to place a product in front of people and turn them into consumers. Microsoft is doing well with Windows and Office because people are comfortable with them, but they haven't got a clue when it comes to introducing new products. When Microsoft finally does bring out a tablet running Windows 8 they need to capitalize on the market they were first to, but was opened up by Apple.