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Slideshow: Motorola Droid vs. Apple iPhone 3GS

The Verizon Wireless spokesman didn't disclose sales figures.

Mark McKechnie an analyst at Broadpoint AmTech, put the number of Droids sold between last Friday and Sunday at about 100,000, or roughly half of the 200,000 Droid phones that Motorola had initially supplied to Verizon stores. McKechnie told Bloomberg.com that the early sales figures are "encouraging."

However, some analysts disagreed with McKechnie's conclusion. Roger Entner, an analyst at Nielsen Co., said in a telephone interview that selling only half the initial supply of Droids over the first three days is somewhat troubling for Verizon, and even more so for Motorola, which is staking much of its wireless phone future on Android devices like the Droid.

"Selling 100,000 is a little troubling, since the Droid is supposed to rival the iPhone," Entner said. "The iPhone sold multiples of that amount in its first weekend for the original version."

Entner said that Verizon subscribers are supposed to be "starving for a great device, and the Droid is really a great device. The lack of masses wanting to buy this thing is a little bit troubling, especially after a serious TV ad campaign."

Entner suggested that sales might improve as potential customers learn more about Droid's impressive capabilities. He noted that a Droid TV ad now running features stealth fighter bombers dropping pods that contain Droids, which leaves viewers uncertain about the device's capabilities. One character in the ad, he said, wonders what the device is. "That uncertainty is the same reaction every consumer has," he said. "People still haven't gotten what the Droid is supposed to be."

Entner said there is nothing that seriously speaks against the device, even concerns about Droid's flat keyboard . "It's a very good device and as close as you can get to being the iPhone. And Verizon is the best network, so there's no reason not to buy the device," he added.

Ken Dulaney, an analyst at Gartner Inc., said that time will tell whether Droid sales surpass expectations. He said that Verizon's inability to sell out the first weekend's supply could have been due to consumer worries that the device weighed more than an iPhone and concerns about its flat keyboard.