As expected, the iPad 2 launched yesterday to long lines outside Apple Stores and other retailers, which reported selling out of the coveted tablet within hours.

Analysts reported that the iPad 2 could sell anywhere from 500,000 to 1 million tablets during its opening weekend, toppling over last year’s 300,000 iPads, says the New York Daily News.

“It looks to me like it’s going to be a very strong launch,” analyst Brian White of Ticonderoga Securities’ told the Daily.

Those who were lucky enough to snag a spot at the head of the line were guaranteed to get their iPad, while many others were told by stores that they were sold out. At the Apple Store in San Francisco, which had a huge supply of tablets following last year’s noted shortages, the line went all the way around the city block and sold out of the Wi-Fi version of the iPad 2 with a few hours of opening, which left disappointed customers with the only option of buying the more expensive 3G iPad from Verizon. Even customers who went online saw shipping dates for iPads go from days to weeks, reports Cnet.

On the other side of the country, at New York’s Fifth Avenue Apple Store, many had been waiting there since Wednesday night in the hopes of snagging an iPad 2. “It’s been a real fun atmosphere out here, even when we were all freezing and soaking wet in the middle of the night,” said Andrew Christian to PCworld. Christian who had been in line since 6 p.m. Thursday was 11th in line and guaranteed a chance to get an iPad 2.

“I’m excited by everything [about the iPad 2]–the faster graphics, the processors, the cameras, the thinness, even the Smart Covers,” added Christian, who already sold his iPad on eBay a few weeks back.

The new generation iPad which is said to be thinner, lighter, and faster has several improvements, and has the same price tag as its predecessor, ranging from $499 to $829 depending on storage needs and whether it would connect to regular Wi-Fi or 3G.