It is simple to write a test page using a new functionality that was announced or was discovered by Mike Williams. I been doing that many times within a few hours from the publishing of a new feature.
Sometimes you just got an idea and write a page for study and publish it. People mail you positive feedback. It is rewarding, useful and fun.
Writing an api extension is totally different. You have to think about all the developers that are going to use your code. You have to write functions that have useful and useable I/O. You have to write clear code with descriptive variable and function names. You have to comment your code clearly. You have to follow general code writing conventions. You have to follow general comment tagging conventions. You have to write a reference. You have to write useful example pages. You have to make a page that describes the extension. You have to monitor and react feedback on group. Still you will get a lot of personal email.
Writing a library of api extensions sounds like something that is not intended for any intelligent creature.
I took the challenge. zmarker.js library will be announced in a few days.
Writing an API is like something from Moon or Mars compared to my 'library'. Now I do respect the Google maps api people even more than ever before. They are doing some unbelievable work.
P.S. From the beginning of the api group: Many of the first posters were disturbed that the marker is ugly. How did they find the right group without a vision.