What does the bug/idea reporter do?
It is simply a convinient way of communicating with me. Think of it as a built in e-mail sender for communicating directly with the developer.
How does it work?
It sends a message to a webpage, and that page sends me an e-mail. Pretty simple really.
Do I have to give you my e-mail address?
Only if you want any kind of reply. Otherwise it is entirely anonymous, other than the IP address of your computer (or gateway) showing up in my http logs.