Hello, i have never used apt pinning but decided to give it a go today. I am running Squeeze, and am trying to apt-pin one program from testing. When i go aptitude safe-upgrade before installing the program, just to make sure it's working like desired; it says i have x amount of upgrades and would i like to proceed. I know that these upgrades aren't coming from the stable branch because when i have the testing repo commented out, update my sources, and try i have no updates.
Is this normal behavior, or have i obviously reconfigured something?

Unless you post the contents of /etc/apt/preferences /etc/apt/apt.conf and /etc/apt/sources.list no one can really help you.

Also a useful command:

Also mixing stable and testing binary repos is a bad idea and you will usually run into problems at some point. If you want a package from testing, have a look in backports first to see if it's available there. If not then you can backport it yourself: http://www.debianuserforums.org/viewtopic.php?f=9&t=127

You are confusing holding something back (pinning) to pulling something from testing/wheezy or squeeze-backports (apt-get -t squeeze-backports install package-name).

oh ok, thankyou for clearing that up with me.