Here are my men. ( pretty difficult to single out a particular bowler )
Shane Bond shud be the pick of the lot for this WC. Though he has been plagued by injuries, he still is a threat to any batsman. Cant really remember when a batsman had actually dominated him. With sheer speed & swing he will definitely hav a say during the WC, especially on the flat tracks in WI.
Mohammad Asif of Pak seems to be a bright prospect. His debut series against India was a blinder of an opening, though he was playing at home. After a stunning performance in the tests he had economical outings in almost all the ODIs.
Brett Lee is another bowler to watch out. Though not at his best in the recent past, he has the capability of running thro any batting line up with sheer speed. He is the main bowler for Australia especially when McGrath is sidelined for personal reasons. ( But i think McGrath will be returning to team well on time for the WC)
Pollock & Murali, as usual, are going to be the most economical bowlers in the WC.
( Murali's 10-0-99-0 shud be considered as a once in a bluemoon event and shud not be given that much importance. )
Harmison/Flintoff/Jones, for England, are all capable of turning the tide in their favour.
Well for India, i dont think any bowler is going to be that devastating for the other teams to worry about. Kumble can be the man, if picked for the WC. I dont know why the hell he is not finding a place in the ODI side, especially when Bhajji is not performing.