Apple's Chain Reaction

Updated from 7:27 a.m. EDT

According to conventional wisdom, Apple's (AAPL) resurgence is due almost entirely to the popularity of the iPod.

But the company's success lately may have as much to do with something more prosaic: Apple's rapidly expanding chain of retail stores.

The stores have given Apple the chance to showcase its products, and not only the iPod but also its line of Macintosh computers. The stores may be a significant reason Apple has gained share in the computer market.

The company's retail strategy is "an important part of Apple's success," says Crawford Del Prete, senior vice president of research at industry consulting firm IDC. "Clearly, Apple's products are experiential in their nature ... they're something people want to go and touch. That's something the stores provide."

But if the stores have boosted short-term sales, they may weigh on long-term results. That's because retail-chain growth inevitably tends to slow as stores age.

Apple's stores are still relatively young on the whole, but that likely will change in coming years as future store count slows.

"Growth does tend to level out," says Craig Johnson, president of retail industry consulting firm Customer Growth Partners. "Nobody's totally immune from it."

Apple's strategy for its retail stores perhaps takes on a greater importance after the company and Hewlett-Packard(HPQ) terminated their iPod reselling agreement last week.

Though H-P was responsible for about only 8% of iPod unit sales last quarter, it did provide a larger retail distribution network that Apple will have to replace through other channels.

People have had their doubts about Apple's stores from the onset, something that inevitably drew comparisons to Gateway's (GTW) failed store effort. Gateway closed its retail division last year as part of an effort to cut costs.