Prototip 1.2.6 has been released, adding a few custom events to the library that should make life a bit easier.
The custom events 'prototip:shown' and 'prototip:hidden' can now be used to call functions when your tooltips open or close. You can observe individual tooltips, groups or all at once. See the Prototip website for demonstrations and code examples.
I've also refactored the library in some places making things a bit faster then before.