Display Requirements: "...linking @usernames to the appropriate Twitter profile, displaying appropriate Tweet actions (e.g. Retweet, reply and favorite) and scaling display of Tweets appropriately based on the device. If your application displays Tweets to users, and it doesn't adhere to our Display Requirements, we reserve the right to revoke your application key."
User Token Maximum: "... we will require you to work with us directly if you believe your application will need more than one million individual user tokens."
Maximum API Call Limit: "... Most individual API endpoints will be rate limited at 60 calls per hour per-endpoint.... There will be a set of high-volume endpoints related to Tweet display, profile display, user lookup and user search where applications will be able to make up to 720 calls per hour per endpoint."
API Authorization: "... we will require every request to the API to be authenticated."