chromium
Are there differences between this Chromium PPA (https://launchpad.net/~chromium-daily/+archive/stable) and the one in the Universe repository?
Are there reasons to choose one over the other? Since the PPA is maintained by Ubuntu developers I assume it's as safe as anything coming from the Universe repository.
There are some key differences between Google Chrome and Chromium. First off, Google Chrome is a commercial closed source product made by Google which is based on the open source Chromium project.
Chrome is not available in the default Ubuntu repositories as it's not open source, however Google makes Chrome available through their own 3rd party repository. Chrome is updated by Google directly, as they run the entire repository and update Chrome on their schedule. Since it doesn't need to be redistributable and open source, Chrome includes things that we can't ship in Ubuntu out of the box, like Flash and H264 support (See the Ubuntu promise). However you can install this support with a few packages (see below).
Chromium, being open source, is available in the Ubuntu repositories. This is maintained by Ubuntu developers and goes through our Stable Release Update process. Chromium has a release process exception, which allows the team to upload a Chromium build as soon as a new upstream release is made.
There really aren't any proper "releases" made of Chromium, so Ubuntu developers base their build on what stable version of Chromium the stable Chrome build is based off of. Fabien Tassin has a blog post about this process that goes into much more detail.
The following packages in Ubuntu install the codecs and features in Chromium that you can find in Chrome:
Really it depends on what you want. If you trust Google to not break your computer and like the convenience of Chrome then you can use that; if you want an open source browser that is the basis of Chrome that is peer reviewed by Ubuntu developers and doesn't require 3rd party sources then you want Chromium.
This Wikipedia page outlines some of the security/usage tracking differences between the two browsers.
The PPAs above are not being updated at all. Alex Shkop has taken up responsibility to keep a better, more updated PPA set for chromium. They include:
Note: The above PPAs are only for 12.04 at the moment.
You can download the continuous builds from here. This will get you the last bleeding-edge chromium revision which passed the test suite.
To install them, just extract the zip file somewhere (I use ~/apps/) and run the chrome binary inside.
Best Answer
The PPA package is updated to the most recent version (in the upstream stable line) potentially every day (not every day in practice, because the stable line doesn't update every day).
The package in the universe repository is only updated if there's a security issue. Unlike most pacakges, the security updates to the Chromium package bring in fairly recent versions of Chromium, presumably because backporting the security fixes is hard. Still, the universe repository is updated a lot less often, so the PPA gives you a more up-do-date system at the cost of making frequent downloads and system changes (it's less stable, in Debian terms).