NDS should jump on the opportunity right away. He'd be a great acquisition, but not a DP of course.
Follows what he said about Drogba in that podcast posted above. Getting another forward is EXTREMELY complicated, which is why he doesn't want to do it as long as Marco is here. Cause when you have a forward thats good enough to start every game, you got to play him, and that messes up with the whole tactical scheme of the team cause all of a sudden you play two forwards, one less in midfield, less protection, less posession, less width etc etc etc.
Remember also that if you sign a player now you pay a full cap hit and full salary.
I am pretty certain that they will wait till summer. there are too many advantages not to:
-Half price DP hit
-Less money spent overall/less money wasted on overlapping with Marco
-less complication with the existing(still in flux/untested) formation
-A much larger and more talented player pool to choose from post WC
-time to see how this group does and assess to choose the best player, as well as deal with injuries and under performers in one shot.
They BETTER sign him, he's a need, and the best hometown player on the planet. Impact aren't the Habs, they need to give the fans a bone once in a while to keep the buzz going and put people in the stands.