Of course one of the coolest things about Twitter right now is the client applications, particularly the mobile/iPhone ones. I use Tweetie 2 on my iPhone every day. Wouldn't it be cool if you could get all your blog subscriptions and post to your WordPress.com blog from apps like Tweetie? Well here's an early Christmas present... We've enabled posting to and reading of WordPress.com blogs via the Twitter API. Any app that allows you to set a custom API URL will work.
By creating a custom implementation of the Twitter API, WordPress can now leverage the developer community's expertise and familiarity with the Twitter web service. In addition, most existing applications that target the Twitter Platform can now integrate with WordPress just by changing the base URL of the web service calls, either with a very simple modification of the code, or by specifying the API root or end point in those applications that have that option, like Tweetie 2.
This new service is not intended to compete with Twitter, but rather to complement the WordPress "mega-blogging" platform with Twitters "micro-blogging", as Matt Mullenweg, the founder of WordPress, explains:
New forms of social media, including micro-blogging, are complementary to blogging.
One of the many uses of Twitter is to link to and promote your blog posts. (And other people's blog posts.) As we grow, so do they, and vice versa. I blog when I have something longer to say, like this. I tweet when it's the lowest friction way to talk to my friends, or get distribution for something longer I did somewhere else.
It's not really a "versus," it's an "and."
Custom implementations of existing APIs are nothing new - Wine has been providing the Windows API on Linux for years. However, it does raise some interesting legal issues. Can an external API use the trademarked names, like Twitter and ReTweet, as a Function name? Is it possible to reprint the existing Documentation? Currently the Twitter Terms Of Service does not deal with these situations, although there is an interesting discussion on Google Groups that could address some of these questions.
With new APIs being created on an almost daily basis, developers will certainly appreciate not having to learn yet another API when targeting the WordPress platform. This move could also mark the beginning of the Twitter API as a de facto standard in micro-blogging.