Your MyGet username is a critical data point in our systems, and we do not support changing your username at this point.

If you feel strongly about changing your username, there is a process that involves creating a new account with the desired name and transferring the feeds. But before transferring your feeds to the new account, verify that your new account has the proper subscription level to support the private feeds and quota of your current account.

For more information about adding a feed owner, see the MyGet Documentation article: http://docs.myget.org/docs/reference/security#Adding_a_new_feed_owner