I think some console guys would have more hours than this, but then again they have had 2 extra months.
For PS3, as a rough guide we can go by the number of matches played. (Although of course this does not include career)
Most I have seen is
@chaman82 with almost 700, I am guessing they would either be T10 or T20, so he must have a minimum of at least 700 hours, but considering he has played many T20's and longer formats I would say he has passed the 1000 hours mark.
And Chaman82 is also a PC player, so my bet would be he would have the highest number of hours playing DBC easily.