Yes yes yes, we know the Halo 3 beta for Crackdown purchasers is delayed, and you can all rest easy in the knowledge that we have that knowledge.

In short, we know, and so does Bungie, who are working on the problem with the Xbox Live people as we speak. Frank himself says so:

Folks are reporting problems downloading the Halo 3 Beta via Crackdown this morning. We have alerted the appropriate Live authorities and they are taking care of the problem as we speak. More news as it comes in.

Everybody just breathe. There's some lovely morning television on. Make yourself a cup of tea, give your mother a call and tell her you love her...you know, all the things you won't be able to do for weeks once you get into the beta. Michael Fahey

Crackdown Delay: We Know! [Bungie.net]