In an announcement for SharePoint 2016 Release Candidate, the future of InfoPath and SharePoint Designer was briefly addressed in the FAQ towards the bottom of the post.
- "InfoPath 2013 and SharePoint Designer 2013 will be the last versions of those products." (still)
- "Support for InfoPath 2013 and SharePoint Designer 2013 will match the support lifecycle for SharePoint Server 2016, running until 2026."
- InfoPath Forms Services is still solidly supported through SharePoint 2016 lifecycle
Given that in 2013 Microsoft was rumored to be moving away from SharePoint Designer and attempting to throw InfoPath over the closest cliff, I'm very happy to see both of these tools recognized as part of the core value inherent in SharePoint.
Apps may be touted as the next great thing but the products that have supported productivity for years aren't fading any time soon. I wouldn't be surprised to see solid replacements for these products released by Microsoft in the next two years.