Twitter clients
A detailed (actually even a brief) look at the field of Twitter clients for different systems leads to an interesting observation: There're not only more but especially far better Twitter clients available for iPhone than for any other device. Take Tweetsville or Tweetie as the dominant examples. They're a joy to use, offer great functionality and one can just feel the attention to detail and thought gone into their development. A look at Mac OS X or Windows, on the other hand, reveals just mediocre clients which lack a lot of functions I'd take for granted, given the size of the userbase and importance of Twitter.
There is no simple monocausal reason to explain this. It might in parts be the (monetary) appeal of the App Store. Another aspect might be a strong usage of the standard Twitter website as a substitute for unnecessary advanced clients. I do think though, that the primary reason is a direct hint at the latent needs, people solve via Twitter. Even more, I do think that the current state of Twitter clients offers a glimpse at the future of Twitter (or Microblogging, for that matter): Twitter is the archetypical mobile application. Currently, a lot of people still twitter while they're browsing the web. Publishing liks to interesting pages. I do think though, that there'll be more and more mobile tweeting. Think about it - as soon as Twitter moves beyond being just a tool to publish links; as soon as you start talking about your life, politics, business or local news; that is: as soon as you start using Twitter as it was intended to be, you'll most likely need it when you're not at home. The Mumbai terror attacks offer an insight into such a usage scenario (and I will use this example in more posts to come, as it serves as a very good example to understand the nature of Twitter).
This, of course, doesn't mean, that there's no need for a sophisticated desktop client. I'm pretty sure, that The Killer Client is already in the works (presumably for Leopard). The interesting conclusion to draw from the above observation is that, in the future, Twitter might very well become ubiquitous.