Personally, I mostly trust downloading programs from the software center, and usually stay clear of PPAs.
Do programs go through a process of going from a ppa to becoming part of the universe repository in the software center?
In the software center, it says
Canonical does not provide updates for System Load Indicator. Some updates may be provided by the Ubuntu community. for some programs.
So if a bug is fixed for that program, do I have to wait until the next Ubuntu version, or will the bug be patched next time I run my Ubuntu update manager?
This may be related to the question (not sure if I should edit the original question)
I noticed, some PPAs have related projects.
They are both maintained by the same people.
Would the first one be a bleeding edge version of the application, where as the second one is related to the package that you can download from the software center?