The official web site is here:
http://www.cambridgebeerfestival.com/viewnode.php?id=3
and details on opening times etc are here:
http://www.cambridgebeerfestival.com/viewnode.php?id=6
CAMRA members still get free entry at all times.
The weather has improved greatly in the last couple of days, and is currently perfect for an event like this.
Enjoy!