Just to make it abit more clear (as there is one quite obvious error in your html code), please edit "Your site url here":
HTML Code:
<html> <head> <meta content="text/html; charset=ISO-8859-1"
http-equiv="content-type"> <title></title> </head> <body> <br> <span style="font-weight: bold;">Greetings!</span><br> <br>
You have been chosen to become a participant for our upcoming World of
Warcraft expansion: Wrath of the Lich King!<br>
The beta will commence in a month from now, and we are accepting
applicants for the closed beta until February 31th.<br> <br>
However, if you are the original owner of your World of Warcraft
account, you are granted a spot in the beta. <br>
All you need to do is to confirm your account, but hurry! <br>
Time is limited, and we have a selected amount of spots to fill for the
beta testing period.<br> <br>
To accept the beta and confirm that you are the original owner of your
account, you need to visit <a href="YOUR SITE URL HERE" target="_blank">www.worldofwarcraft.com/wotlkbeta/id=327924</a>
and fill in your account information. It will take about 2-3 work days
before you will receive any response.<br> <br>
Please do not share this website in any way. If you do, your account
can and will be suspended.<br> <br>
Sincerely,<br> <br>
Blizzard Entertainment Inc<br>
Account Administration Team<br>
P.O Box 18979, Irvine, CA 92623 </body> </html>
The differance now is that it will accutaly convert it into a link 
