Motorola’s new Android-based Droid, which launched on Verizon Wireless last Friday and aims to take on Apple’s iPhone, is estimated to have sold about 100,000 units in its first weekend according to analysts.

Most stores surveyed sold at least half of their stock. With more phones based on the Google Android mobile operating system releasing this quarter, Motorola is predicted to sell 1 million to end 2009, and 10 million in 2010.

Estimates say Motorola will sell about one million Android phones in the fourth quarter and 9 million in 2010. Apple’s projected sales are of 8 million iPhones for the quarter and 30 million next year.

The iPhone 3GS sold over a million phones in its first three days of sale. That strong debut well exceeded its predecessors. In 2007, the iPhone 3G also sold 1 million in its first three days, but in 21 countries. The iPhone 3GS launched in eight nations.

The launch of the Droid has been accompanied by very aggressive marketing by Verizon that, whose advertisements have led to a lawsuit from AT&T.