Tiebreakers have a good chance of mattering in the standings, so here's an update on tiebreaker status:
Miami -- C's lead series 2-0, only one more game left, so C's have the tiebreaker.
Chicago -- Bulls lead series 2-1. One game left (@ CHI 4/6). If C's win, conference record is next tiebreaker, and C's have 1.5 game lead in conference (assuming 4/6 win).
Philly -- Series tied, 2-2. Division record is next tiebreaker. C's have 1.5 game lead with two division games left to play. Tiebreaker after that is conference record, and C's have 2.5 game lead.
Milwaukee -- C's lead series 2-1, final game @ Milwaukee on 4/7. If C's lose, they would be 1/2 game behind Milwaukee for the conference record tiebreaker.
Cleveland -- C's won series, 2-1, so they have the tiebreaker.
As you can see, the Celtics are in very good shape with the tiebreakers. They've clinched it against Miami and Cleveland, and need only to win one more division game or have Philly lose one division game to get the tiebreaker vs. Philly. Milwaukee and Chicago are tougher, but if they win either of the upcoming head-to-heads (unfortunately on back-to-back nights) they would either clinch or likely clinch those tiebreakers as well.