Differences between rpm-based distros

I wanted to run Yahoo Messenger on Suse 10.1 but the Yahoo web site provides packages for other distros than Suse. I tried to install Yahoo Messenger anyway, and miracle, it worked. It brings to mind the question of what requirements a package must meet to be able to run on Suse. How can I tell a non-Suse package will be able to run on Suse (10.1) successfully? Rich