Practice shows that those who speak the most knowingly and confidently often end up with the assignment to get the job done.

Here again, the key is to be a contributor of substance.  If you speak up when you are knowledgeable on a particular subject, you will inspire the confidence of your management and you will get assignments that will allow you to demonstrate your worth.  However, if you speak up when you are not knowledgeable, you may well sign on for an assignment you can’t handle.  

This is a great example of how a willingness to volunteer, coupled with a “no fear” attitude (slight exaggeration, but you know what I mean), got me some great assignments.  But beware, there is a huge downside to volunteering if you are just “winging” it!