Clearly, Twitter's strong suit is its extremely impressive integration with SMS for cell and its fleet of widgets for smartphones. After all, when is there a better time to tell the world that you are on your way to get a latte than while you are actually driving to Starbucks? OK, that was snarky -- obviously, business people are on the move, and the ability to quickly disseminate important tidbits of information is a big deal to them. So, some of them, at least, are turning to a popular consumer platform for doing that.
Seems to me, that's the catch. Sooner or later, information other than "noise" is going to become common in Twitter, and just as with IM, businesses and IT are going to be faced with a lot of really important data being generated in the most unstructured manner possible. Forget for a moment about the general informality of a media that can induce a state official to publicly bash on a college basketball player. From an IT standpoint, it's a knowledge management (and quite possibly, compliance) headache of near-Biblical proportions.
At some point in the near future, somebody who owns one of those old-school blogging platforms (say, a Google) will integrate (or buy, as the rumor mill has it) the ability to send SMS one-liners and push notices to smartphone widgets from the same interface. Seems like a logical extension of any productivity suite, including Microsoft Office -- still sounds a little redundant to e-mail, but blogs are conveniently searchable and are made of structured XML, so they tend to play very nicely with other data stores. And a busy CEO could use the same interface to informally announce to the company that "Sales Rocks!" on the train and to write a more detailed monthly blog post about sales performance the following morning.
Finally, if this kind of mobility is important to your company, get your guys on a mobile data plan ASAP. Those texting fees will eat you alive. That is, unitl Google makes them a "free" part of Apps.