In upgrading to the new ThinkPad X1 Carbon Broadwell ultrabook, I'm debating whether to switch back to Fedora after having used Ubuntu for a number of years on my main production system after some falling out with a few less then stellar Fedora Core releases back in the day (of course, on test systems, there's plenty of Fedora around here but this is just about deciding on my next main OS for business tasks). In waiting for the new Broadwell ultrabook, I've been running some fresh Ubuntu and Fedora Linux tests on some other laptops/ultrabooks in the office.
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.