Looks like somebody is trying to get money or your pass0owrds by foul means suggesting that you have three months Skype account due via PayPal. I googled this as i had such fishy email sent to me this morning and hey presto i knew it. The only subscriptions i have are with Ebay and LJ.
Details here -
http://community.skype.com/t5/Security-Privacy-Trust-and/Fake-emails-from-paypal-re-Skype-subscription-BE-AWARE/m-p/3701177#M37784 So be warned, if you get the email do not click.