Yahoo! internally has quite a lot of support for PHP, with extensive developer knowledge that lends itself well to helping communities using our APIs / products. Currently there are two API formats available, PHP and ActionScript. In much the same way that many social networking containers leverage off of external developers to extend the community with APIs that they feel would lend well to the developers as a whole, we would definitely aide developers with support if they wish to create their own APIs, be they in Perl, Ruby, etc.
Alternate APIs are definitely in the proposed pipeline but contributions from external developers would provide the community with greater depth and technical support would always be available on these forums for those endeavors.
Jonathan LeBlanc Sr. Software Development Engineer Yahoo! Developer Network