BlackBerry 6 was designed with touch devices in mind. A lot of the on-screen navigation tools developed by RIM for BlackBerry 6 may be duplicated on the optical trackpad, but the experience feels like it is missing something.
The basic navigation, menus, and home screens are all laid out the same way, but interacting with them is difficult. The way RIM has set up BB6, each home screen has its own app drawer that slides up to reveal more apps. The home screens are access on the Torch by swiping the screens sideways.
On the Bold 9700, the side-to-side navigation often gets mixed up. You might intend to slide to the next home screen, but instead the cursor slides across the apps listed on the bottom of the page. Same for vertical navigation. Opening and closing the app drawers was especially irksome.
Without the ability to use your finger on the screen, it definitely takes longer to navigate through the screens and menus. It's just not as fast to use as on the touch-based Torch.
Some features are missing entirely. For example, there's a press-and-hold user interface trick on the Torch that brings up a menu tray for taking actions. No such fun on the 9700.
It is, however, still a major improvement over BB5.x.
One of the better additions is the notification bar. Similar to the way the notification shade works in Android, this bar holds all your alerts -- new emails, BBMs, text messages, missed calls, etc. Tap it, and it drops down to show you the details about those alerts. If you want to ignore them, just tap again and it slides back up out of sight. If you want to interact with any of the alerts, select the message that interests you and it will open.
The benefit here is that you can quickly see if any of the messages demand attention or can be ignored. You can do this without opening the full messaging, or voicemail, or email application -- it can all be done from the home screen.
Even though RIM has committed to bringing BlackBerry 6 to some existing handhelds, I would say the BB6 platform is still better for touch phones. Hopefully RIM will get around to bringing more touch phones to market in the near term.