@pcuser, @eye0 and @kcarney: welcome aboard!
About more three or four can still join. I'll be closing the openings tomorrow.
For today, one feature I'd like to talk about the new winbuilder is the native support of the relevant Windows file formats that is not depending on Windows API or drivers.
For example, it is possible to create and extract files from WIM archives. It is possible to extract files from ISO images, it is possible to create bootable ISOs without needing any external tools.
It is possible to create Windows shortcuts (.lnk) with full access to all parameters. This is very handy to create shortcuts that are only valid once they are used inside the booted Windows PE.
Last but not least, we packed this winbuilder with native support for reading and writing registry hives.
Experimentally, we even added support for creating empty VHD files as well. The idea is to one day move from WIM archives to fully formatted VHD images without need for any Windows/Linux tools.
The outcome of this native support is the added speed and fine control over the building process. There are no drivers involved. There is no need for users to have administrative permissions to edit the registry or mount WIM archives, there is even no need to use Windows for building a Windows PE. Anyone can now build a great Windows PE boot disk straight from a linux server machine if they wish.
This kind of independence helps to build reliable bootdisks since we depend much less on the host platform for supporting the critical parts of the build system. If one day new Windows versions no longer support the registry or WIM archives, we will still keep working just fine.