Notes don't seem to maintain an order. For example, in one pad I have notes numbered 4, 5, 2, 1, 0, 2, 3, 6. Finding the note I want in the new version of xfce4-notes is very very difficult.
Right on that, also that there isn't anything to allow sorting the notes. It seems I totally left that beside. Finding the note you want however is accessible through the window menu, it's possible to right click the window title or simply click the window icon.
Btw. I consider to save the order, in fact that's a bug. However for sorting I don't see anything simple to add, I had like to listen on suggestions for this part.
I made a change in revision 7717 but not yet tested to add the option for the tabs again, it doesn't allow to sort the notes however.
fcfe6ce..5b258ff Note that there is no way to reorder the tabs, while it may be easy to add, but I don't think this is useful for notes. If someone wishes it, please open a new br.