While the original Bold used a trackball for navigation that was sunk into three separate panels that served as the device's call, menu, escape and end call buttons, the new Bold employs a more efficient trackpad that sits in a single piece of smooth material that forms its call and navigation buttons. (The call and end-call buttons are no longer green and red on the Bold 9900. Instead, they're both translucent white.) The new Bold's trackpad also has a glowing ring around it that makes it easy to use in dark environments, another first for a BlackBerry, and a nice addition overall.
The Bold 9900 also has a new mute button on its side, between the volume up and volume down keys, both of which also serve as media controls when music or video is playing. And it has two very small charging panels on its base for use with a BlackBerry Charge Pod--the Bold 9000 had similar, larger panels on its lower sides.
The Bold 9900's 2.8-inch, 640x480 (287 PPI) display is impressive as well, and colors look both vivid and bright. The Bold 9900 is the first "candy bar" style BlackBerry with both a touch screen and "physical" QWERTY keyboard. And though it's going to take me a while to get used to using both the screen and trackpad for Bold navigation, I was impressed with how responsive the display was to my touches, taps and pinches. And I look forward to seeing what sorts of new touch-gestures RIM adds in the future.
On the software side, RIM's Bold 9900 is the first BlackBerry smartphone to run the upcoming BlackBerry 7 mobile OS, which packs a variety of cool new features and enhancements, as well as a slightly different look and feel due to some modified icon sets. Most notably, BlackBerry 7 packs a new voice-activated universal search feature and a speedier Webkit browser.
Honestly, BlackBerry 7 doesn't really feel too different than BlackBerry 6, and that's somewhat unfortunately, since RIM is marketing it as a major OS update. But as mentioned, I was only able to spend 20 minutes with the device, so there could be more to the software than I saw in my brief time with it.