Microsoft will be offering more upgrade promotions for operating system Windows 8, which is expected to debut sometime in the fall. The company has announced the price of its Windows 8 Pro upgrade: $39.99 for online updates and $69.99 in-store.

This offer is available for users currently running on any version of Windows XP, Windows Vista or Windows 7, according to the Windows Team Blog. This is different from the offer that was announced in January, under which those purchasing a new Windows PC before Windows 8 launches will be eligible to purchase the next-generation software for $14.99.

The newly announced upgrade offer will last until Jan. 31, 2013, and applies to any current Windows users. Microsoft says the offer will be valid in 131 markets, and that more details are to come as the release date approaches.  

For those running on older versions of Windows, an upgrade assistant will help users transfer files, settings and apps from Windows 7, files and setting from Windows Vista, and files from Windows XP. This upgrade assistant also alerts users as to whether or not their PC is ready to run and install Windows 8.

After installing the upgrade, users can add Windows Media Center for free via the Add Features option.

The online version of Windows Media Center can be downloaded, but a backup DVD can also be purchased for $15. For those who prefer to build their own machine or run a virtual one and aren't upgrading, the Windows 8 Pro System Builder will be required.

We believe that your upgrade experience in Windows 8 will be a breeze by offering a faster experience, a single upgrade path, and compatibility from prior versions of Windows, the blog post reads. We've continued to listen to our customers and have expanded the ability to download to over 100 countries and 37 languages.

It was also recently reported that Hewlett-Packard, one of Microsoft's closest hardware partners, has no plans to produce a tablet that will run Windows 8. This further signifies Microsoft's shift into a new market share with its upcoming releases, an analyst has said.

For them to say they're skipping this is a big deal, Michael Gartenberg, an analyst at Gartner Inc., told Bloomberg. If they can't get HP on board, that's pretty indicative of the fact that things are different and the old loyal partners can't always be depended on.