RIM co-CEO Jim Balsillie actually declined to show off the his company's tablet today on the Web 2.0 Summit stage, but in private he was more than kind, treating us to a nice long glimpse at the BlackBerry PlayBook in a quaint hotel hallway. We only got to heft the one-pound slate for a few seconds, but we got the basic feel of the device in the hand -- warm to the touch, solid if a little plasticky, with a responsive glass touchscreen up top and a bottom that's mildly rubberized. Balsillie didn't bother to locate the "module cavity" for us, but he did try to explain where those 5300mAh lithium ion cells might hide -- we suspect the CEO exaggerated only slightly when he told us "it's all battery and glass inside." He then wrenched the device forcefully from our unprepared hands (at least that's how we like to think it went down) and proceeded to let us film a brief film showing off the QNX and Air-based OS juggling a spreadsheet, photo gallery and some beautiful underwater footage all at the same time. Hit the break for that hastily-shot video.