Lorna Mitchell has new post today pointing out the release of both the slides and the audio from a presentation she gave at the PHP UK conference (back in February of this year) about some of the best practices in API design and development.
I really enjoyed giving this talk, since I work so much with APIs and enjoy sharing my ideas. The audio is now online so if you missed the talk, feel free to have a listen. You can also see the slides (on slideshare) and also read the series of blog posts I wrote on this topic which originally inspired the talk.
Lorna has also posted slides for several other of her web services talks including Working with Web Services, PHP and Web Services and Archtecting Web Service Applications.