Apple could even bundle these apps in a sort of iCloud Pro subscription, allowing Windows users to get a larger amount of iCloud storage along with the iWork apps for a monthly fee. This would be similar to Microsoft's Office 365, which includes 1TB online storage for $10 a month (for five home users). Of course, if Apple were to offer a plan like that, they would have to be competitive with Microsoft; $10 a month is currently the price Apple charges for 500GB iCloud storage, and Mac users would be happy to see this price drop.
There's another possibility, and that's Photos for Windows. The iPhone's camera is one of its key selling points, and Apple constantly highlights this, even running an ad campaign called Shot on an iPhone 6. Windows users who take a lot of photos might appreciate being able to manage and edit them on the desktop, rather than having to export them and use a different app.
Either way, it seems that Apple wants to get the attention of Windows users to show them something. I'll be tuning in next Tuesday to see what's new.
Sign up for CIO Asia eNewsletters.