I had a chance to briefly see the BlackBerry PlayBook at HIMSS 2011, but then I had a chance to spend some time and play with it recently when I was at the airport. The device is small and light and my first impression was: "this is simply too small."
Keep in mind that I use an HTC ThunderBolt smartphone that has a 4.3" screen. So, when you have a slate tablet that has a 7" screen, it doesn't seem much bigger than the ThunderBolt. The Samsung Galaxy Tab also has a 7" screen, so this device is similar in size compared to the PlayBook.
I think it's rather ironic that RIM is positioning the PlayBook as the "The World's First Professional-Grade Tablet." Why did they name it the PlayBook? Seems counterintuitive to me.
The PlayBook is really slim and has a solid feel. You'll notice that the device does not have a "home" button like the iPad. You'll need to play around to figure out how to navigate back to the home menu. Try a few on-screen gestures and you'll quickly figure it out. If you can't figure it out, try swiping up, swipe down, swipe left, etc. The new mobile Operating System is not like your typical BlackBerry. This new OS is much closer to HP webOS (formerly Palm webOS).
It was nice to see Flash integrated into the browser. Be prepared for some small (or tiny) font when you pull up the menus since the screen is only 7". Also, the battery is not user replaceable, but you should not have any problems lasting all day (approx 7 hrs).
The biggest flaw with the PlayBook is the tiny round button that powers the device on (technically, it turns the screen on). I'm sure that RIM will use a larger button in future models. This tiny little power simply doesn't make any design sense to me. Think about how often you power on/off a device.
I think RIM did a nice job with a first tablet, but I'm predicting that a larger tablet will become the industry standard for "professional" or "enterprise" functionality. A 7" screen works for consumer devices mainly focused on email, casual web browsing, or entertainment. I think that most business users (and medical professionals) will prefer something that has a 9" or 10" screen. I predict that RIM will be releasing a larger model that also has a bigger power button and this will be more popular than the 7" model among professional users.