The adoption of systemd in Debian has caused quite a ruckus, but it has other ramifications. For example, Ubuntu will soon use systemd by default, most likely in Ubuntu 15.04. The community has put together a great wiki page that explains the differences between upstart and systemd and how you use it right now.
This isn't a straight forward Ubuntu is better than Xubuntu or Xubuntu is better than Ubuntu article.
This article will also show Ubuntu users how to get to a base XFCE desktop and also how to install the complete Xubuntu desktop.
Ubuntu and Xubuntu are created for different purposes and what I aim to highlight here is when and why you would use Ubuntu and when you would use Xubuntu.
This comparison is similar to the three-way NVIDIA GeForce graphics card comparison from Monday but just testing the Maxwell-based GeForce GTX 970 and GTX 980 graphics cards while running the latest binary drivers on Windows and Linux. As with the other end-of-2014 Windows vs. Linux benchmarks, Windows 7 Pro x64 with all available system updates was used and on the Linux side was Ubuntu 14.10. The latest NVIDIA Linux driver is the 346.22 driver version while the latest Windows version at the time of testing was the 347.09 driver release.