With virtual keyboards so common, it's should be easy for alternative, more efficient keyboard layouts to make headway, since, as we've all heard, the default QWERTY layout was designed to slow typists down. So why aren't more devices (or at least the iPhone) giving you options, like the Dvorak layout? From the Hartford Advocate:

If you consider all of the ways that technology has changed, even in the past four or five years, it seems strange that the majority of us continue to use something as outmoded and inefficiently designed as the QWERTY keyboard. Our things are constantly being tweaked and updated and resold to us as more comfortable, more useful, easier to manage and better organized. But keyboard-comfort improvement is basically limited to gel pads and little flip-out booster legs to prop the thing up. Unless you’re willing to make a drastic change, your keyboard options are slight, limited... The WSJ story reported on the frustrations of Dvorak users with their iPhones, which didn’t come with a Dvorak keyboard option.

I'd be willing to give Dvorak a try, but I just don't see this other alternative being useful:

What will more likely become standard-issue might be a virtual version of the Fast Finger Keyboard that came out a few months ago, which a lot of bloggers dismissed as stupid. It has function keys that say “ASAP,” “BTW,” “BRB,” “LOL,” “IMO,” etc