Facebook is the sneakiest. You probably didn’t even notice, but Mark Zuckerberg & Co. have changed your e-mail address on the social-networking site from something you actually use to one ending in @facebook.com.

Don’t believe me?  See for yourself.

“As we announced back in April, we’ve been updating addresses on Facebook to make them consistent across our site,” a Facebook spokesperson told Mashable. “In addition to everyone receiving an address, we’re also rolling out a new setting that gives people the choice to decide which addresses they want to show on their Timelines.”

First spotted on Saturday by blogger Gervase Markham, the email address you once listed as your point of contact is now hidden in the site’s database and your assigned @Facebook.com address is highlighted for friends to see.

If you ever changed your Facebook vanity URL, that serves as the prefix of your Facebook email address (i.e. Facebook.com/John.Smith would be John.Smith@Facebook.com). For those that never added a vanity URL, Facebook has assigned numbers to serve as your email account name.

This is a problem if you actually want people to contact you at your desired e-mail location. Thankfully, restoring that information is relatively painless.

If you want to switch your email contact information back to what it was, it’s easy to do. Visit your Timeline or profile page and select “About” under your contact information. You can then hide your Facebook email address from the contact page and elect to highlight another email address.

Nice try, Facebook. We anxiously look forward to your next in-the-dead-of-the-night move.

[H/T: Mashable]