By Katie Marsal

Published: 09:00 AM EST

A Wall Street analyst who recently reported that Apple was torn between using dual-core processors and quad-core processors in its next-generation iMac line now believes the company will adopt both.

Kaufman Bros. analyst Shaw Wu told clients on Monday that AppleInsider's latest report on iMac shortages is "consistent" with comments from his supply chain sources that the iMac is due for a refresh in the March or June quarters.

"In our experience, when Apple sends an advisory to its channel partners of limited availability and inventory of existing models are drawn down, it is highly likely that a product refresh is within a few weeks," he said.

Wu generate some headlines exactly one week ago when he reported that new iMacs were almost ready for prime time but were being held up for "business reasons and a potential small technical hurdle."

Specifically, he said Apple was in the "midst of figuring out whether to power the new iMac with Intel quad-core processors or more high-powered dual-core processors with larger caches."

In his note to clients today, Wu now claims to be hearing from his sources "that both types of processors will likely be used," which would "makes sense as this helps Apple create better tiers within the iMac family, utilizing quad-core for the high-end, and dual-core for mid-range and low-end."

Still, it's unclear from precisely what information the analyst is drawing his conclusions. Historically, Wall Street analysts sport a lackluster track record in predicting Apple's future hardware directions, and therefore readers may want to take the latest predictions with a grain of salt. That said, Wu has on at least one occasion defied the odds.

Nevertheless, the Kaufman Bros analyst emphasized to clients the crucial rolled played by the iMac in Apple's Mac story. He estimates sales of the all-in-one desktops comprised 25 percent of the Cupertino-based company's Mac business during the December holiday quarter, adding that the systems can at times represent as much as 36 percent of Mac sales during strong periods immediately following a product refresh.

"We believe having both strong portables and desktops will help the Mac sustain its above-market rate growth rates and maintain its momentum in this tough macroeconomic environment," he said.

Should iMacs go quad-core, Wu speculates the move would also spark an update to the Mac Pro, which is currently offered in both quad- and eight-core configurations.

"As Apple mentioned briefly on its earnings call, Mac Pro sales have become less important and less attractive in this tough economic environment," he told clients. "However, we think a refresh utilizing upcoming Intel 'Nehalem' 8-core processors (and with two enabling a 16-core) would bring it better price performance and help jump start this highly profitable segment."

Wu maintains a Buy rating on Apple shares with a $120 price target.