Leopard leaping in June

The release will come at the tail end of spring, which ends June 21, enabling Apple to meet its original shipping estimate.

As recently as January Apple had been targeting a ship date of end March—as noted by multiple Think Secret sources and other media reports—but the company elected in recent weeks to move the date back. Sources privy to the reasons behind the June ship date could tell Think Secret the details only off the record, however.

"Leopard is shaping up to be a more significant release than anyone expected, with much more to come than any of the developer builds have led on," one source said.

Also scheduled for a June release now are new versions of Apple's iLife and iWork suites, which will pack extensive Leopard-dependent features. Sources say Apple continues to toy with the idea of bundling one or both suites with the new operating system free of charge in an effort to further play up the extra value and features Mac OS X offers over Microsoft's new Windows Vista.

In addition, there is a reasonable chance that Apple will drop its yearly naming convention for the software suites entirely, sources report, suggesting "'07" could be replaced with "Leopard Edition", or a similar naming convention that would free Apple from being tied to date-specific versions that appear older in consumer's minds as the calendar rolls over.

Competitor Microsoft plans to release the next version of Office for Mac in the second-half of 2007, for example, but will assign the software a 2008 label. Apple's next version of iWork, meanwhile, is poised to compete even more directly with Office with the addition of a new spreadsheet application.