According to an EA forums user, Tom Goldberger (EA’s UK publicist) has emailed him that:
The Beta should go live on June 21st for 360 owners. Further confirmation will be posted on the official site.
If this is true, it’s not so bad – except for the Xbox 360 BFBC2 VIP players like me, who have missed the possibility to kickstart the demo early (even on PS3).
Until now, the feedback in the forums is mitigated. A lot of haters, but I guess the people who like the beta wouldn’t waste gameplay time posting! Reportedly, the most serious issues until now are the PS3 version freezes. The gameplay, as we can also guess by the videos, is more arcade, more intense than BFBC2, in the veins of Modern Warfare.
UPDATE: It has been confirmed that the Xbox beta will be available on the 21st.