How do software updates work?
I'm using ubuntu and any now and then new updates are offered for installation. However I've noticed these updates don't necessarily offer the latest update for any one package, but why?
For example, today, under ubuntu 11.04 I'm beeing offered to update the linux kernel from version 18.104.22.168 to 22.214.171.124, but on my secondary computer running xubuntu 11.10 the kernel version is already 3.0!? Other examples are the nautilus package which remains at version 2.32 in ubuntu 11.04 and which is already at version 3.2.1 on xubuntu 11.10, or mono JIT compiler sticking to 2.6.7 in 11.04 but already at 2.10.5 in 11.10.
So, does anyone has a clue as to why these updates are updating my system to old versions?