No, Burger King hasn't been sold to McDonald's, although Burger King's Twitter profile was hijacked earlier by hackers who spoofed a McDonald's logo and photo.
Elements of the Anonymous collective under the auspices of LulzSec appear to have claimed credit for the attack, after writing "We just got sold to McDonalds! Look for McDonalds in a hood near you... For the record, our password was not 'whopper' or anything!"
The hackers also reportedly posted tweets that included racial epithets to Burger King's some 83,000 followers - which soon jumped by about 25,000 to more than 108,000 after the incident.
The latest Twitter incident follows a security breach earlier this month that revealed the usernames, email addresses, session tokens and encrypted/salted passwords of 250,000 users.
As such, Twitter has been planning to make logins more secure by introducing two-factor authentication. Essentially, two-factor authentication blocks access from a new device or internet address, even when the correct password is used, unless the user also enters a numerical code that's sent to their phone.
Of course, Twitter wouldn't be the first company to lock the stable door after the horse has bolted in this way: Dropbox, too, introduced two-factor authentication after a security breach last summer. Google already offers it as an option for Gmail.