This story has been updated with Sterne Agee's latest estimates for December quarter iPhone 5 sales NEW YORK ( TheStreet) -- Apple's ( AAPL) new iPhone 5 won plaudits from analysts and investors alike when the device was launched at an event in San Francisco last week, laying the foundations for a record debut weekend. Early on Monday, the Cupertino, Calif.-based firm confirmed that the iPhone 5 had shattered the previous pre-order record set by the iPhone 4S. Apple's iPhone 5 pre-orders topped 2 million in the first 24 hours that the phone was available, double the number for the iPhone 4S. AT&T ( T) also described the iPhone 5 as its fastest-selling iPhone ever in a statement released on Monday. Massive pent-up demand, coupled with overwhelmingly positive reviews of the new phone, suggest that Apple's on to a massive winner with the iPhone 5. Brian Marshall, an analyst at ISI Group, told TheStreet that he was impressed with the new iPhone when he picked it up for the first time at Apple's launch last Wednesday. "When you put that sucker in your hand, it's like, 'Wow!' " he said. "You have a 20% larger screen coupled with an almost 20% thinner and 20% lighter form factor -- typically, these things don't go together. It kind of reminds us of the first time we picked up an iPad." Sterne Agee analyst Shaw Wu was also won over by the redesigned iPhone, particularly its 4-inch screen. "At first glance, it looks the same size as the iPhone 4S, but when you use it, particularly in landscape mode, it's clearly a bigger screen," he said. In addition to its larger screen, aluminum redesign and new software capabilities, other key features of the iPhone 5 include its 4G LTE capabilities and an A6 processor, which is both faster and smaller than its predecessor, the A5. Marshall also sees Apple's promise to have the iPhone 5 in 100 countries and on 240 different carrier networks by the end of the year as a major advantage. By way of comparison, when Apple launched the iPhone 4S last October, the company said that it would have the phone in more than 70 countries by the end of 2011.