Yes, I know Ubuntu and Xubuntu already come with Chromium in their official package repositories, but sometimes it does help to have the official/commercial version installed in addition to the Open Source one. I actually both installed right now, plus Firefox and Vivaldi. You could almost think I'm some sort of web developer or something.
The Google Chrome installation instructions for 14.04 on Ubuntu Portal also work fine for 15.04 with one wrinkle. If you use the installation via PPA method, you need to run the following command to actually install the stable version of Chrome:
sudo apt-get install google-chrome-stable<br />
The page above lists the command as
sudo apt-get install google-chrome but that doesn't work for me on 15.04.
I would recommend installing Chrome via PPA as that will integrate into the automatic update process. One less thing to think about when keeping your machine up to date.