Shares of Apple Inc. reached $600 for the first time ever Thursday morning in early trading, pushing the company's market value over $555 billion.

On the eve of sales of the new iPad, which has received positive reviews, analysts set new price targets for the technology company's shares, which had passed the $500 mark less than one month ago.

Michael Holt, senior equity analyst with investment firm Morningstar Inc., said the $600 mark is not significant in and of itself, but it's interesting because it reflects the momentum of Apple's success.

"The more important factor is how many iPhone and iPads they're selling, and the reaction to latest product announcement," he said. "Those are the things going well for the firm. That's why the stock is pushing forward."

The company's new intraday high hit $600.01. With a 52-week low of $310.50, the stock has soared over the past year, leaving analysts wondering when the meteoric rise will stop.

When asked to comment about the company's outlook, Holt said "it's definitely not downhill from here."

"The near term momentum for Apple looks unstoppable," he said, but down the line, there are questions regarding how Apple will be able to fend off competition with lower price points.

Holt said one way they will be able to capture market share in countries with lower per capita income such as China and India will be to keep older versions of their products with lower prices.

Apple reported stellar quarterly results in January, after selling 37 million iPhones and 15.4 million iPads in its first quarter, which ended Dec. 31.

The Wall Street Journal points out it took only 23 trading days for Apple's stock price to jump from $500 to $600. Prior to that it only took 34 days to go from $400 to $500.

Around 10:04 a.m. eastern time, the stock ticked lower to $591.29, up about 0.29 percent.

The world's most valuable company, based in Cupertino, Calif., has sold out of its original new iPad pre-order stock online, but shoppers can obtain the device in stores Friday.