Looking at the page source the only Javascript that is running is Google Analytics so we are probably safe. Your antivirus probably doesn't like http://1337day.com/.
I copy/pasted the text and sent it to my gmail address (to archive it), and gmail rejected the message with "Our system detected an illegal attachment on your message.". (There was no attachment, but just the main part).
So it might be possible that some parts of the code match existing malware.
It's almost certainly just flagging the long blob of %uXXXX escapes as characteristic of heap spray exploits, not detecting any specific exploit.