The big gadget blogs are scratching their heads this morning over the sudden disappearance of Microsoft's Mac software site, Mactopia, but it looks like it's just a problem with the site -- not signaling anything ominous about Microsoft's Mac Business Unit, which makes Office and other Microsoft programs for Apple computers.

Sheridan Jones of the Mac BU posts on Twitter: "engineers working on it - expect it back online today."

The timing isn't great: The outage is no doubt getting heightened scrutiny because of last week's layoffs, giving people reason to wonder if Microsoft is making some kind of big shift related to its Mac unit.

However, that doesn't appear to be the case. It's not clear if there were layoffs in the Mac BU, but I'm told there have been no major changes in the unit's overall product strategy or direction.

Update, 12:05 p.m.: The site is back up. In the process of looking into this, I also asked Microsoft about how last week's cutbacks are affecting the Mac BU. Here's the company's response:

"While the group eliminated some positions, the essence of MacBU will not change. We are committed to delivering the industry standard in productivity software on the Mac. We are well under way with development of the next version of Office for Mac, and we recently released a beta version of Entourage for Exchange Web Services and will soon release a private beta of the Microsoft Document Collaboration Companion, both milestones in our product roadmap."