Is the font scaling and smoothing better than in Windows 8? I've had issues of blurry text in many applications, including Windows system dialog boxes, when using a high-CPI (high resolution) screen with large/x-large fonts.
It is definitely better than Windows 8 (and obviously 7). All Windows apps are optimized as are the dialogs. However third party apps that still haven't updated with proper support will show the blurry stuff. I think Steam is one of those cases.
I mentioned in my Win10 review, even the setup process is high DPI ready which was a welcome surprise.