If you are like me and bought a copy of Crackdown on the Xbox 360 purely for the entry into the Halo 3 beta, you’ll want to hear this news.  This post at Microsoft confirms the beta will only run from May 16th until June 6th — after that you are S.O.L.

REDMOND, Wash. — April 10, 2007 — Microsoft Game Studios and Bungie Studios today confirmed the multiplayer beta of ‘Halo® 3′ will debut to audiences worldwide via Xbox LIVE® on May 16 at 5 a.m. PDT and run through June 6 at 11:59 p.m. PDT. Coming exclusively to the Xbox 360™ console this fall, ‘Halo 3’ is the highly anticipated third chapter in the groundbreaking ‘Halo’ trilogy from legendary developers Bungie. ‘Halo 3’ lets gamers experience Master Chief’s greatest battle as he launches an epic mission to stop the Covenant, destroy the impending Flood threat and ultimately save mankind.