In an interview with The Loop Apple has announced that with the release of its new OS later this summer, it will discontinue development of its photo editing app Aperture. It will be replaced in the new OS by an app called Photos, which will also enlace iPhoto. Apple have stated that there will be a migration path for Aperture users to Photos, although as the later seems to be largely cloud based, this may be challenge for those with big libraries.
Apple have stated that they will continue to offer compatibility updates for Aperture, but will not be developing the app further. Although unconfirmed, it would make sense for Adobe to offer a migration path for existing Aperture users onto Lightroom.