Last night Adam Mosseri, Head of Instagram, quitely announced the next step in the integration of Threads into the Fediverse. In addition to being able to follow Threads accounts from Fediverse/Mastodon accounts, we can now reply to and like Threads posts. Threads are taking a quiet, incremental approach to Federation, but seem genuinely commited.

From About Threads and the fediverse

If you turn on sharing to the fediverse, users on other servers can search for and follow your profile, view your posts, interact with your content, and share your content to anyone on or off their server. On Threads, you’ll be able to see the number of users on other servers who liked your post. You'll also be able to see and like their replies to your post.