Microsoft's Upcoming Email Change
If a mail address becomes unusable, you should ask via ticket a change from support. It will not be new to them. I changed an unusable mail address to a new one before, but only support can do so.
The actual email addresses aren’t changing. It’s only the website you go to for reading/sending emails that is changing, you’ll log into www.outlook.com with your existing hotmail address.
Even if they wanted to, they would not be able to change the hotmail addresses to outlook, because names like “johnsmith@hotmail.com” would already be taken with the @outlook.com addresses.
ArenaNet Communications Manager
I believe that Emissary is correct and that the email address will not change, but if you do need help in the future, simply contact Support and they will lend a hand.
Communications Manager
Guild & Fansite Relations; In-Game Events
ArenaNet
Thank you for the replies.