The questions for the Celtics are whether they can afford to do that trade. They really have no one to send to N.O. and would have to eat Okafor's contract (and/or possibly Ariza's).
If they do that they have:
PG: Rondo, Teague (#22?)
SG: Bradley, Moore (resigned)
SF: Pierce, Buford (#51?)
PF: Garnett, Drummond, Hollins (resigned)
C: Okafor, Steisma (resigned), Johnson
If they can pull it off and resign Garnett the above isn't bad. Huge hole at the backup positions if the rookies/sophomores don't pan out. They do get much younger though and have some really solid potential in Teague and Drummond. Plus you know Teague can throw an alley-oop. If they could afford Ariza with as well that would be a huge bonus.
I think Hollins, Steisma and Moore can all be pretty cheap resigns. Garnett would be a big question mark. Ray is obviously not likely to resign (though with the above team, he would fit in perfectly at the backup 2). Pietrus would be a nice resign also.
If they can't swing that deal, they likely have to draft either Fab Melo or Royce White or someone like that at #21.