My thoughts:
1) Gerald Wallace will either be a collar around our necks or a valuable player. He'd been a very good player for several years prior to completely stinking last year. He was an all-star in 2010, and it was deserved, and he probably could have been one for several years prior. In the following two seasons he was still a solid an valuable player. He completely hit the wall this last year, and I don't know why. He admitted as much that he had no confidence. But he's only one year removed from seven years of good-to-great basketball, and is certainly not over the hill.
2) It's almost certain that at least one other team will be involved. This team (or teams) will serve one of two purposes. They will either have additional contracts to dump to clear salary in pursuit of some free agent, and will give us additional picks and/or young players for the service of taking on these obligations (for instance, Dallas), or they will instead take most of what we get from the Nets in exchange for players we actually want (for instance, Atlanta). This deal, even if the Nets and Celtics agree on what their giving each other, is far from done. They're getting their negotiations out of the way so that the Celtics can find other teams to fill one of the other two roles, but in a way that makes it less complicated that a three-or-four-way negotiation. Also they want to clear it with KG, so that there isn't the risk of him nixing it at the last minute, but rather he nixes it now or never. If you're a third team looking to dump salaries, you don't want to be hung up on the whims of KG.