So I have been requested to consider over another persons code in WordPress with very little time before launch date... Usually I'd refuse but it is a fascinating project. I'm a very good Drupal programmer but haven't much experience of WordPress.
So I wish to know, what's the distinction between creating a Drupal module along with a Wordpress wordpress plugin / widget? Would be the systems sort similar? API's, hooks etc? Would you learn to get it done kind of good per week?
If you are a great Drupal (and PHP) programmer I am confident that you could pickup Wordpress programming per week. The secret in this scenario is really a to pickup a bestseller/e-book that provides the fundamentals so it's not necessary to google around for that absolute basic principles. After you have acquired the fundamentals I believe its nearly writing decent PHP code, looking at the code of other (similar) modules and checking API references.
Here are a few links (if you can most likely google it on your own...) http://codex.wordpress.org/Plugin_API
Some training http://codex.wordpress.org/WordPress_Lessons
Books using blogging platforms https://www.packtpub.com/books/wordpress
You may particularly wish to checkout https://www.packtpub.com/wordpress-plug-in-development/book