Microsoft is currently presenting the event for Windows 10 and is expected to announce news products hardware but also preview the next version of Windows 10 (codenamed Redstone 2, which is scheduled for release next spring).
Rumors also suggest that Microsoft will announce a new one All-in-One PC (maybe even some models) with the commercial signal of Surface. Some new accessories are also expected to be introduced such as the Surface Dial, a standalone device to help users use a digital pen. We're also waiting to see the new Surfaces.
On the software side, Microsoft is expected to announce new edition of Paint which will probably just be called Paint 3D.
Paint 3D will be a UWP app that will contain all the tools of the classic version, but is expected to work with 3D as well objects, as we are close to Windows Holographic, which we might see appear as well.
Watch the live event from the following stream