You have 48 hours. Wait, make that 45.
ArenaNet has just launched a beta sign-up page for Guild Wars 2 at https://beta.guildwars2.com. The beta sign-up page is only going to be up for 48 hours (until Friday, February 24 at 6:00 PM GMT), so excuse me while I sign up.
Read More: http://www.mmofront.com/sign-up-for-the-guild-wars-2-beta.html