iPhone Typing and Alternatives to Traditional Tactile Feedback

I read an article a couple weeks ago discussing a study that found iPhone users can type as fast as users of phones with traditional keypads, but they make more mistakes. I found part of these results quite surprising. Given my own experience with the iPhone, I’d certainly agree that iPhone typing is more error prone. However, I wouldn’t have guessed that iPhone typing speeds are on par with other qwerty devices, even with disregard to errors. For me, it seems to require so much more focus and attention to type at all on the iPhone, and I am much slower at typing on the touch screen than I was on my blackberry.

In searching for information about alternative forms of tactile feedback, I stumbled across Immersion, a company that offers tactile feedback for touch screens. Their interfaces add vibration feedback to onscreen interaction: “varying the frequency, waveform, amplitude, and duration of the vibration.” They claim such feedback can decrease “glance time”. This could certainly be useful useful for interacting with interfaces while on –the-go, or multi-tasking in other situations. I'd love to try an Immersion interface out! I wonder if it would improve iPhone typing, or if typing is too granular of a task?...