By Katie Marsal

Published: 12:40 PM EST

Inventory of MacBook Pros has become severely constrained over the past three weeks, with some reseller now reflecting backorder status on the soon-to-be refreshed Apple professional notebooks.

Apple retail partner and online reseller Best Buy has recently run out of 15-inch models, and lists on its online store wait times of one to two weeks for availability.

Meanwhile, other large Apple resellers have managed to maintain availability of the Intel-based Core 2 Duo notebooks, but have informed AppleInsider that their flow of incoming and forward looking orders has decreased significantly over the past month, ahead of a product refresh.

"With each passing week, [MacBook Pros] are becoming harder and harder to come by," said one source, who spoke under the condition of anonymity. "Orders are still trickling in, but in quantities half those of December."

AppleInsider reported last month that Apple had delayed the planned MacBook Pro refresh by approximately four weeks in the months and weeks approaching Macworld Expo, but that the new models were still due to arrive shortly.

Among the enhancements expected as part of the impending release are processor upgrades to Intel's recently introduced 45-nanometer "Penryn" Core 2 Duo processors at speeds of up to 2.6GHz and the addition of multi-touch trackpads across the entire product line.