It's nice to be able to scroll through your appointments or emails on the lock screen. You get more interaction with these apps than in iOS's lock screen notifications. But you can't add widgets to an account that has a PIN or password requirement imposed by Exchange or a mobile management tool -- only the clock widget is available. That's no doubt a security issue, but it greatly limits the utility of the widgets for business users. However, if you imposed a PIN or password yourself on the device through the Settings app (and if your server doesn't require its use), you can add widgets to the lock screen.
I was also frustrated that the screen would fade out while I was using the lock screen widgets. Android doesn't detect that you're using the screen to keep the tablet awake. Also, the selection of lock screen widgets is tiny. At this point, lock screen widgets is more a toy feature than a compelling one.
Note that to access the new multiuser and lock screen widget capabilities, you need to update the "Jelly Bean" software. Although Google says devices ship with that update, the loaner unit Google sent InfoWorld did not have it. Worse, the Settings app claimed the software was current, even though it was not. After we contacted Google, the update appeared an hour or so later. That may be a coincidence, but if these features don't appear on your unit, check for updates periodically.
The third new capability is the enhanced Camera app, which provides the kinds of controls over white balance and high dynamic range that you'd expect on a digital camera. These controls appear in a circular overlay menu onscreen. They make the Camera app much more capable than iOS's Camera app, though the menu overlays are often hard to distinguish. As with iOS, there are now postproduction tools in the Android Camera app such as cropping and color filters (but no red-eye removal as in iOS).
The fourth addition is support for the Miracast wireless streaming standard that builds on the Wi-Fi Direct standard, providing a way to share video to TVs and other devices. Many Android devices have supported the DLNA standard, but it's unevenly implemented by both device makers and home entertainment hardware vendors, making it an unreliable mess. Thus, Google has moved on to Miracast as its hope to match what Apple's proprietary AirPlay protocol enticingly delivers.