If you contact Skype's support, they can actually delete your account directly, but before they do that, they ask you to replace your profile information with gibberish.
And I bet if you search that gibberish, it still shows up. And I bet if you recover account on that, it'll still work. Likely, all they're doing is changing the password.
I would never trust any of the "data-hoovering" companies to actually really delete all of your data, even if they say so.
(And in the case of Skype, it's terribly obvious that they want to prevent you from deleting data. In the age of NSA mass surveillance, this absolutely makes sense.)
