At 4teamwork we have dozens of different Plone sites running, old ones and new ones. Since we cannot migrate all the older sites to the latest version of Plone, we need to patch them, too. To further complicate the issue, for a site running e.g. Plone 3.0 more patches have to be applied than for a fresh install of Plone 4.3.
Hotfixes are usually backported to patch releases of older versions of Plone. This makes it a little more complicated to decide what hotfixes really need to be applied for a specific Plone installation.
In order to address this issue and in light of the upcoming patch day I created a website that tells you what hotfixes need to be installed on your Plone site.
Give it a try: http://jone.github.io/plone-hotfixes/ and leave some feedback if you want.
I wish you a happy patch day ;–)