Piper Jaffray analyst Gene Munster tells clients that his initial estimates of 900,000 iPads sold in the June quarter and 2.7 million in calendar year 2010 “may prove to be conservative” and that Apple is selling every iPad it can build.

As reported by All Things D (http://finance.yahoo.com/news/Munster-Apple-is-Selling-allthingsd-4182584461.html?x=0&.v=1), Munster thinks Apple will sell between 200,000 and 300,000 iPads this weekend — comparable to the 270,000 first gen iPhones it sold at launch. And he thinks the chances are good that the company will sell out of the tablet device.

“When Apple began taking pre-orders customers could pre-order for home delivery on April 3 or in-store pickup on April 3,” Munster told clients. “A week before the launch (on March 27) the company pushed back the shipping date to April 12 and ended the in-store reservation program for the launch. And in preparation for the launch, on March 31 Apple retail stores began calling those with iPad pickup reservations to confirm the reservation. We believe these signs indicate that initial demand for iPads was stronger than the company expected, and/or minor supply issues have slightly constrained availability for the launch. We believe the supply constraints are minor because the new ship date is not a significant delay. Ultimately, both strong demand and somewhat constrained supply appear to be resulting in the fact that Apple is selling every iPad it can build.”