How to Change your email address on YouTube
This video shows how to change your YouTube email address. It may not work for users whose accounts were made before the Google update.
Log into your Google account
Click on account in the upper right hand corner
Click on change email
Type in your new email and password. This may only work to change to non-Gmail accounts.
Log into that email account, click on the email from Google, and click the link to accept the change.
To make sure it changed, sign in to YouTube, click on account>email options and see if it is the email you switched to.