Apple Computer's ( AAPL) first-quarter earnings announcement later Wednesday may be lacking in drama, but it certainly won't be without an audience. CEO Steve Jobs already announced many of the headline numbers, including revenue and number of Macintosh computers and iPods shipped , at last week's Macworld conference. But investors will still be scrutinizing the earnings announcement to get a sense of where the company will go next. Although there's eagerness to hear actual financial guidance, other items may draw as much or more interest from investors. Among them: the company's operating margin in the just-completed quarter, any word on its retail store build-out , and any hints of new products to come. "The fundamental momentum of this company is becoming more secure, so the guidance may have less impact on investor sentiment than it has in the past," says Tony Ursillo, a buy-side analyst at Loomis Sayles & Co., which holds Apple shares. As revenue has ballooned over the last two years, so too has the company's operating margin. Ursillo and other investors will be looking to see if that trend continued in the fourth quarter, when the company's sales significantly overshot its revenue guidance and the Street's expectations. Much of Apple's stock and financial rebound has been driven by the iPod and its investment in retail stores. Analysts will be looking to see if the company has a hit new product up its sleeve that might succeed the iPod as a growth driver. They'll also be looking to see just how big the company's retail chain can get. "Not to take anything away from the iPod or the iPod nano -- those are hot products that deserve to get attention -- but the one thing we think is underappreciated by the Street is Apple's retail stores," says Dave Bujnowski of Coburn Ventures, a consulting firm. "Any comment they have on whether it's going to be 160 stores by end of year -- or 170 -- that's what I'm going to be interested in," adds Bujnowski, who manages a mock portfolio in which Apple is one of the top holdings. To view a video preview of Wednesday's call, click here .