We've recently had users complain about receiving messages that emulate our emails. We are aware that some people have been creating emails to appear as if they were sent from YouTube, and these seem to propagate phishing websites.
If you think you may have received a suspicious link, hover your cursor over the link to see where it's redirecting you (look in the lower left corner of your browser's status bar). If the link doesn't direct you to youtube.com, it's not from us.
If you've already clicked a suspicious link, you may want to scan your computer with anti-virus and anti-spyware software to discover any malicious software that may have been installed on your computer without your knowledge.