From the /etc/apt/sources.list there are two repositories that are commented out like this:
## +++ Backports & Proposed (Ubuntu Unstable) +++
I enabled them and reloaded synaptic and there were 54 additions & updates. Now, these are "Proposed" and "Unstable" so I did not install them. But they are included in the sources.list even if they are not enabled by default, so does anybody enable them and update or is it better to just ignore them?