The official way to contact the WordPress.com support team is through the “Feedback” tab in the Dashboard of your WordPress.com blog, or on the WordPress.com forums.
The WordPress developers have chosen to use the bbPress software over phpBB because they developed bbPress. bbPress is a bare-bones, fast, forum system, and is a work-in progress. It supports registered users, categorization, tags, topic history, resolved/un-resolved status, and a search engine (when properly implemented).
Please read Using the Support Forums!
Subversion is the online program used to track changes and upgrades to WordPress for developers. See Using Subversion for more information. There is also an online browser for the WordPress Subversion repository.
Definitely! See WordPress in Your Language for information on existing translations, and Translating WordPress to find out how you can help if your language’s translation is missing or needs improvement.
Yes. WordPress Coding Standards has a list of coding standards used by WordPress core developers, plugin developers, and theme authors.