I don’t know Twitter’s mission statement, but to me it seems like it should involve enabling stream-of-consciousness communication. When I look at heavy Twitter users (especially those with iPhones), it is close to stream-of-consciousness — it seems like they’re sending every other thought to Twitter. But it’s not stream-of-consciousness for most people, there’s too much overhead in posting to Twitter.
It seems to me that if Twitter had some spare cash, it would be wise to look into developing some more advanced technology. The iPhone is very close to wearable computing, but I’m sure there’s some clever ideas in the wearable computing area that could be adopted and branded by Twitter. There’s a great opportunity for them to pull a trick like Apple did with the iPhone, and bring this technology to mass-market in a nice slick package. It’s a natural extension of their current business, and it’s a technology that’s coming — a nice time to catch the wave.