Microsoft is continuing to bang the OneNote note-taking drum.

The company is preparing to release a free, full-fledged OneNote for Mac application "soon," according to my sources. The Verge's Tom Warren is hearing the same.

I'm hearing OneNote also will be released as a free app for desktop Windows, as well. Right now, it's part of the paid suite of Office applications (though the OneNote Web App and the Metro-Style Windows 8 versions are free.)

Microsoft already offers versions of its OneNote app for the iPad and iPhone, as well as for Android phones , but not yet for Mac.

Microsoft will make available a new OneNote Clipper service and Office Lens as part of the updated free releases of OneNote, my sources are saying. The Clipper service will sync links between PC/device browsers and phones. Office Lens is an app that uses optical character recognition (OCR) and a smartphone camera to allow users to sync snapshots to the cloud.

I'm betting the new OneNote for Mac will be part of the updated Office for Mac suite which is expected to arrive later this year . Microsoft may roll out the OneNote version for Mac separately and earlier, however, as it has done with its Metro-Style/Windows Store version of OneNote .

Microsoft is battling other note-taking applications, especially Evernote, in the quest to be users' cross-platform note-taking app of choice. As part of its campaign, Microsoft is also planning to open up more of the OneNote programming interfaces to encourage third-party developers to write applications that build on OneNote, my sources say.

I've asked Microsoft officials for comment on these OneNote futures. No word back so far.

Update: "We have nothing to share," said a Microsoft spokesperson.