If you're working on a Linux workstation, Docker will spin up and run much faster than either VirtualBox or VMWare. This alone makes it worth switching.
I don't know what the current situation is on Windows or MacOSX. Back when I used them for my own work, the only choice was to run a VirtualBox instance running Linux and then run Docker on top of that. Clearly that solution is more of a lateral move from Vagrant.