You'd know the answer if you'd taken the < 1 minute to read the article. It was mentioned in the opening paragraph.
Yes, they announced it a few minutes ago on I/O
Re:Android now supports Kotlin
by luisramalho on Wednesday May 17, 2017 @02:49PM
(#14361591)
Yes.
Edit: sorry, I completely forgot googleio is today, and i couldn't believe this kind of news comminng ftom non google domain.