With CCPulse Reporting, one can use Stat Server MCR Extention (Specificly eServiceInteractionStat.jar file) .
Total number of e-mail interactions in queue at the requested moment that are being processed.
>> JavaSubCategory => eServiceInteractionStat.jar:EQR Current in Processing
Total number of e-mail interactions in queue at the requested moment.
>> JavaSubCategory => eServiceInteractionStat.jar:EQR Current in Queue