On Raina ~ I think he is ready, he's shown plenty of maturity in this one-day series and although he is only 19, he has plenty of domestic experience unlike Piyush Chawla, who needs more grooming before making the step up. He's young yes, but he's much more experienced than other 19-year old prospects we've seen.
On Bhajji ~ While Powar is a good batsman, Bhajji has done very well as a batsman lately. I know we'd like to think Powar still remains the better batsman overall, but surely "batting" can't be the reason to keep Harbhajan out ... he's been one of our leading batsmen of late.
On Munaf ~ He can definitely blast, but he's far from a "batsman" by the looks of it, really pathetic technique. A potentially dangerous slogger, yes, but I wouldn't count on him consistently resisting good bowling attacks like a Powar, Harbhajan or Kumble can.