What is this “Universal Transaction Platform&#

When I upgraded to version 4.4, I noticed that the installer included a new “Universal Transaction Platform”, so I tried reading the documentation to see what it was for. OK, clearly it’s for doing two-phase commit and other stuff to make transactions consistent over multiple databases, but all the documentation (that I could find) really describes is how to install and configure it. How would you actually use it? When or why would you want to?