What is changing?
Starting February 1, 2016 we will start using 64-bit snowflake IDs for all new instances of the remaining API entities - Users, Lists and Saved Searches. Tweets and DMs are already using Snowflake IDs. Existing IDs will remain valid.
All core entities represented in Twitter’s API are associated with an ID. As per the API interface and documentation, these IDs are 64-bit long. However, some of the entities currently use IDs that are within the unsigned 32-bit limit. We previously announced the migration of some of these entities here back in 2013.
What do I need to do?
If you currently use signed 32-bit integers to track the above IDs in your system, you should update your code to use 64-bit integers as soon as you can.
As usual, please leave any feedback about this announcement in the forum.