In aptitude, when I type g for go, I get amongst the proposed changes, a list of both "Packages being held back (232)" and "Packages being automatically held in their current state (48)". What is the differences between those ?
I suspect their amount is building up with system upgrades, but what should I do with this ? Isn't this causing problem on the long term and is there a way to manage this, other than periodically reinstalling the whole system ?
"Packages being held back" generally means that you've not specifically requested that those packages be upgraded or that you have specifically pinned the versions so that those packages cannot be upgraded automatically. When packages are being held "in their current state", it is because the updates have dependencies on the "held" packages being updated beforehand.
If you would like to to upgrade all of the packages already on your system, then:
aptitude update
aptitude upgrade
If you want to upgrade everything to the current version of the default installation, then:
aptitude update
aptitude dist-upgrade
Hope this helps