Battle for the planet of the APIs by Jeremy Keith — nice piece of writing, it’s worth pointing out that Twitter still includes rel=me links back to homepages, but is increasingly wrapping them with t.co, making them fairly useless.
Whilst I admire RSS as a rallying cry for the openness of data on the web, I don’t like it much, mainly due to it’s DRY violation. microformats2 is the better solution.