Just to be clear: windows 8.1 fixes the DPI scaling issues that were present in windows 7 and windows 8. Currently, Windows 8.1 does scaling identically to OSX: it does so in 2.0 increments as opposed to the 1.8 increments that were present in prior Windows releases. Furthermore, it applies anti aliasing (as OS X does) to any applications which don't natively support scaling in 2.0 increments (most applications do). Any app using the native windows interface will automatically work out of the box. Applications such as chrome, firefox, etc need support for DPI scaling but that shouldn't be an issue since they already support 2.0 increment scaling.
In short, the DPI scaling is basically massively improved in 8.1 as compared to windows 8/7.
People seem to forget that if the application does not support high resolution scaling, you are only going to be left with interpolated images. There is not much one can do until the developers jump off the 72dpi standard.