Apple Nano Not Yet a Mania

But while the retail stores had run out of some versions, Apple's online store was promising to ship both versions of the 4-GB nano in one to three business days and both versions of the 2-GB nano within 24 hours.

That's in sharp contrast with previous iPod products. Soon after Apple released its flash-based iPod shuffles earlier this year, the company warned online customers of an order backlog of several weeks.

Likewise, Wu noted, Apple was sold out of iPod minis for nearly six months after it launched the devices last year. "We may be alone at this point, but we believe matching the super success of iPod mini may be a tough act for iPod nano to follow without some changes," said Wu.

But setting aside whether the nano will match the sales the mini posted last year, it may have trouble keeping up with current mini sales, particularly if consumers focus on how much storage space they are getting for their money. At the same $200 and $250 price points for the two nano versions, consumers can get 2-GB more storage on the iPod mini.

Indeed, on Amazon.com, the various nano versions were being outsold by at least one version of the iPod mini. The silver 4-GB iPod mini was the seventh-most popular item in Amazon's electronics department on Tuesday afternoon. The black 4-GB iPod nano was the top-ranked version of that device in the department, coming in at No. 16.

"We believe iPod nano may cause sticker shock as consumers are not getting more storage for their dollar as they are accustomed to," said Wu. "AAPL may need to either increase the storage capacity to match at least iPod mini ... or keep its storage capacities and cut the price by $50. We believe the former is more likely."