Adobe has released a plugin it promised a while ago to migrate photo libraries from Apple's soon-to-be-forgotten Aperture and iPhoto apps into its own Lightroom. If you're worried about Apple's switch to its own all-in-one photo app, "Photos," or simply want to ensure similar functionality to that found in Aperture, Lightroom has long been an industry-standard alternative. There are, however, a few notes to keep in mind with regard to migrating from these apps to Lightroom.
While many aspects of your catalogues will transfer over, some are still left out in various ways. Color Labels, Stacks, and Face Tags will only be imported as keywords. Yes, your general flags, star ratings, keywords, GPS data, rejects, and hidden files ratings will all transfer normally. But why Color Labels or Stacks couldn't be translated to similar Lightroom color labels or "Collections," respectively, is a little beyond some of us.
Likewise, the tool already has at least a majority of the eleven that have reviewed it quite upset, with some complaining about the fact that Creative Cloud subscriptions seem to be necessary while others simply can't get it to work at all. Also, the plugin will transfer the original photos in addition to copies of the photos with changes you've made, since it is not possible for Lightroom to exactly emulate all of the Apple programs' various algorithms.
If you need a migration solution, Lightroom is still your best bet, unless Apple really comes through with its Photos app due out early next year. Until then, this plugin (or perhaps an updated version still to come) will at least make the transition as painless as possible. You can have all the novocaine in the world, but you're still at the dentist's.