Suspect this stems from a string of questions that the AFPS MPs were asking on the RAFs policy wrt the use of cluster bombs about 9 months to a year ago. A string of emails later revealed that there was, in fact, no policy other than to use them if they were the most effective weapon to take out the target. However it was noted that they were due to be fully replaced by 2010 (? I believe, though the grey cells are fading proportionatly to the amount of grey hair...). The replacement was slated to be brimstone, as it was deemed that it could be carried in large enough numbers to be effective against large numbers of vehicles (soft skinned or armoured).
Not entirely convinced that it could replace all the roles of CBU, but it's a bit more PC in this day and age...