Installing Node with apt-get vs PPA - what's the difference?

apt-get is great for installing stable and tested software, though that implies they are no longer prime-time as you might want.

That is absolutely fine with most software, but sometimes it is better to use recent, less stable, rather than old stable version.

Node.js is exactly the case, where you would prioritize latest version over 'stability', plus you have all rights to doubt version 0.6.12 is more stable than 0.10.26, eventhough the later one was not tested as excessively on ubuntu.

Use PPA for selected software like Node.js, but I strogly suggest to stick to apt-get as long as it is convinient (in node.js it isn't). Being cautionless with installing products from PPA eventually results in your system instability.

The official versions in the apt repository are often older than the ones you get from a closely maintained PPA. With something like Node, the "older" version from the last Ubuntu release can be drastically out of date.

PPAs usually have more recent version of node/nginx/whatever.

For example, in Ubuntu 12.04 LTS repo, nginx version is 1.1.19 and nodejs 0.6.12 while in PPAs they are 1.4.7 and 0.10.26. So "default" packages are pretty old.