Microsoft has delivered a preliminary release candidate for Windows Vista Service Pack 2 (SP2) to testers and is again on track to offer another public preview next month.

Just last week, a Malaysian website, TechARP, claimed that Vista SP2 had been pushed back a month. Wednesday, however, TechARP, which has accurately predicted Windows delivery dates in the past, revised its estimate, saying that Microsoft had "brought forward their release schedule" and would be issuing an "escrow" build no later than Friday.

However, earlier this week, reports surfaced that testers had been told by Microsoft that the escrow build of Vista SP2's release candidate was available for downloading. ZDNet blogger Mary-Jo Foley, for example, cited a section of the e-mail notification, which told testers that the company was not interested in feature feedback, but only reports on "SP2 regressions and confirmation of fixes we've made."

An "escrow" build is a version on which development has stopped but that is handed to developers and testers, who are asked to shake out the code one final time to make sure there are no show-stopping bugs.

TechARP's revised timetable claims that Microsoft will deliver a full-fledged release candidate to the public during the week of 16-20 February, not in March as the site said last week. That will be followed by a release-to-manufacturing (RTM) build sometime in the first half of the second calendar quarter - in other words, before mid-May.

Previously, TechARP had said Vista SP2 would reach RTM - a milestone at which the service pack is officially finished, and sent to computer makers and duplicators for retail copies - as late as June.

Vista SP2 will be released for download from the web at an undetermined date after Microsoft slaps the RTM label on the service pack. In the past, Microsoft has waited to post service packs anywhere from just two weeks after RTM to more than six weeks after.

But with the recent appearance of the first public beta of Windows 7, the follow-up to Vista, already in users' hands, some have dismissed Vista SP2 as irrelevant.

"Who cares now with Windows 7?" asked a user identified as Luis Mazza on a message thread discussing Vista SP2 at the Windows enthusiast website, Neowin.

"I could care less as I just got rid of Vista and I'm now only running 7 beta," added "smooth3006" on the same thread.

One analyst, however, disagreed.

"Service packs always matter," said Michael Cherry, an analyst at Directions on Microsoft, a research firm. "Because service packs make it more efficient to update PCs, they increase the chances that people do deploy fixes and patches."

Microsoft has previously declined to comment on TechARPs Vista SP2 schedule, and has instead reiterated its general timetable for delivering Windows Vista SP2 sometime in the second quarter of 2009.