Here's that Blackberry promo video - the same principles apply exactly to Nokia's E6, for example - even the ill-fated HTC 7 pro, Nokia N97/N97 mini and E7, to some extent?
Pocket-lint report from the HTC 'Frequencies' event in Seattle (more from Rafe at some point, since he was also there.....):
HTC may well have manufactured its last QWERTY keyboard phone after admitting it has no plans to revisit the form factor... the HTC design team spoke candidly about moving away from phones with physical keyboards, with emphasis very much being on touchscreens.
However, only last year we saw the HTC ChaCha, a QWERTY keyboard-sporting handset. Yet even one-button access to Facebook wasn’t enough to convince consumers and the HTC ChaCha received a lukewarm reception. Whether it was the ChaCha’s underperformance that has caused HTC to re-evaluate its road plan it’s hard to say, but Pocket-lint for one still feels there is a place for HTC QWERTY phones.
So perhaps it's safe (and sad) to say that we may never see a followup to the HTC 7 pro in the Windows Phone world. A shame, as it's a unique form factor that (quirks aside) works rather well. There's slightly more chance of seeing a followup to the Nokia E7 in the Symbian world, I think, plus the E6 is still very much a current product. And one that works well in a hurricane when being pounded by teddy bear fluff... [see the video above for explanation!]