RIM held a BlackBerry WebWorks developer event in San Francisco this evening, and while hard news was not in attendance, we did score a number of tidbits about the company's BlackBerry PlayBook. First and foremost, there's most definitely a portrait virtual keyboard in the latest QNX tablet build, and we literally gave it a spin, watching as the landscape layout slowly switched to portrait mode as we changed the slate's orientation. Second, we may have gotten our first hint about what RIM's doing with the recently-purchased TAT -- we overheard that the PlayBook's bezel gestures actually aren't quite finalized yet, and that the astonishingly silent UI design division may be lending a hand. On the all-important subject of battery life we don't have much to add beyond earlier boasts, but a staffer did tell us that RIM's shooting for a "full work day" of juice. Last but not least, we were told that Jim Balsillie's module cavity certainly exists, but it's not the user-upgradable slot or socket we'd hoped -- rather, it's a orifice deep inside the PlayBook for hardware enhancements at the factories where devices are built. Like this one, perhaps? Video after the break.