I’m so much faster with touch than I ever was on my BB. But your comment made me realize how much I’d love a jog wheel where my right index finger rests (top right side) while my thumbs are typing. I’d use it for adjusting the cursor location or press in to select a word for replacement.
What you're describing is how my very first cellphone (a Sony PCS phone, model CM-B1201SPR) operated. It was awesome, and I distinctly remember the mini-grieving I did when I replaced that phone with a Nokia. Snake was cool, but I missed that jog wheel!
And yeah, imagining it already feels right to me as well. I just picked up my iPhone and imagined how cool it would be if Apple took their digital crown, flipped it sideways, and submerged it into the edge of the phone. Sure, waterproofing might be tricky, but they figure that out for other penetrations through the case, so I have faith.
Cursor keys to edit, a scroll wheel to navigate one's inbox, it was a dream that "they" stole from us with RIM's demise.