For me, the best time to buy was March 24th. I got a sweet deal and took delivery about 2 weeks ago. I've been soaking almost every night.
Since you can't buy yours on March 24, 2006 I'd recommend you buy yours tomorrow.
Honestly, I too wonder if some dealers aren't willing to lower prices a bit late in the month and/or late in the quarter. You'll probably get the best deal on a floor model just as the new models are coming out.