Microsoft on Thursday pushed back the release date of Office 2008 for Mac until January, a delay from an earlier promise to deliver the new suite this year.

"It was clear from our June and July quality checkpoints that no matter how hard we tried, we couldn't release our product in time for the Christmas season with the kind of quality we wanted," said Craig Eisler, the development group's general manager, on the team's blog.

The new mid-January debut to retail would correspond with Macworld Expo, Apple's big conference and trade show, which is slated for Jan. 14-18 in San Francisco.

Previously scheduled to ship in the second half of this year -- Microsoft has never been more specific than that six-month window -- Office 2008 will move into release to manufacturing (RTM) status in December, said Eisler, launch at Macworld, and be available to volume license customers in the first quarter of 2008. Microsoft had given no indication that the original 2007 ship date for the suite might slip, although the first Open XML file converters for Office 2004 and Office v. X made a late appearance in May, a month or more past an earlier deadline.

Eisler, who just came on board Microsoft's Mac Business Unit in June, did not give an explanation for the schedule slip. Elsewhere, however, he was quoted as saying Apple's 2006 switch to Intel processors and the ensuing need to move to different development tools, as well as the ongoing struggle with the new Open XML file formats, played parts.

Some Mac users didn't take kindly to the announcement. One, dubbed "p0intblank" on MacRumors' message forums, offered a tart observation: "Microsoft delaying a product? I wish I could've seen this coming." Others on the same thread said this was the last straw, and they wouldn't be coming back to Microsoft. Instead, they would turn to, or continue using, the open source OpenOffice and NeoOffice suites, or Google Docs.

Other development will be shoved aside for now, Eisler added, to focus on Office 2008. "We're in an 'all hands on deck' mode right now to ensure Office 2008 gets finished on time, and so you will not see final versions of our RDC client or file format converters until sometime after we ship Office." A beta of Remote Desktop Connection Client -- a program that lets Mac users connect to Windows systems to access files and run applications on those PCs -- was released earlier this week; an update to the Office 2007 file converter popped up Tuesday.

An invite-only Office 2008 for Mac beta test is currently underway, but Microsoft has no intention of opening that to the general public. Instead, said Eisler, his group will offer what he called "sneak peeks" to users, although he didn't spell out exactly what that might entail.

Prices for Office 2008 have not been set. Current prices for Office 2004 for Mac range from $149 to $499.