Honestly, I think the biggest key to this series is not doubling Howard. While people want to compare him Shaq, he's really something closer to an oversized Alonzo Mourning (meaning he doesn't have Shaq's polished post game). The biggest mistake teams make is doubling him and opening up Orlando's three point shooting. Then, even when they miss, Howard gets the board and the putback, which inflates his stats.
Perk handles Howard better than anyone in the NBA, BBD did a heck of a job on him last year keeping him away from the basket, and Wallace is very solid on him as well. The C's need to guard him one on one, which will take everyone else away.
Jameer Nelson really is no better than Mo Williams. Both are really shooting guards in point guards bodies. The difference so far in this playoffs has been that Jameer has gotten a million open looks, whereas Mo (mostly) had a hand in his face every game. If Rondo stays home on Nelson, Nelson will be about as effective as Mo Williams was in the Cleveland series.