This isn't Bash or Ubuntu running in a VM. This is a real native Bash Linux binary running on Windows itself. It's fast and lightweight and it's the real binaries. This is a genuine Ubuntu image on top of Windows with all the Linux tools I use like awk, sed, grep, vi, etc. It's fast and it's lightweight. The binaries are downloaded by you - using apt-get - just as on Linux, because it is Linux. You can apt-get and download other tools like Ruby, Redis, emacs, and on and on. This is brilliant for developers that use a diverse set of tools like me.

Windows just got cancer.

here's more information on the technical implementation. In short, it's a sort-of reverse WINE - it translates Linux syscalls to Windows syscalls in real time.