Heavensward opening movie it's out but there are 2.55 story spoilers so be warned! 
Other tidbits from the Live Letter last night: 
– The Heavensward main scenario will offer around 50 hours of gameplay – post-release patches will continue to add more. 
– New job quests for existing jobs 50-60, combat, gathering, and crafting. 
– New zones are 50-100% larger than zones in A Realm Reborn. There are nine new areas including Ishgard & Floating Continent. 
– Flying mounts are unrestricted in taking off and landing. Once you “attune” to an area, you can fly there. 
– Dark Knight, Astrologian, and Machinist start at Lv. 30. 
– Multiple new actions for each job have been added. Lv. 3 Limit Break animations aren’t shared, will be unique for each job. 
– Regarding new endgame currency, Allagan Tomestones of Law will have no weekly cap. Allagan Tomestones of Esoterics will. 
– Tier V materia in the final stages of planning. 
– A specialist system for crafters will be added for Lv. 55~ You can spec in three jobs, and use “scrips” to change. There are spec actions. 
– You can become Lv. 60 in all crafters without specializing. 
– At Lv. 60, gatherer classes can discover hidden nodes by using “divine favors” through a “Favor System”. They’re available for a limited time, and are obtained by trading “scrips”. You can collect Red and Blue Scrips at Lv. 60 as a currency for gatherers/crafters. Blue Scrips have a weekly limit. 
– New high-level levequests, FATEs, large-scale FATEs, field enemies, and elite marks have been added. 
– 8 new instanced dungeons. 
– Ravana and Bismarck primals will have a normal and hard mode. 
– New Frontline area, rule sets, and PVP rewards. 
– In Free Company Workshops you can craft housing or craft airships. 
– An expansion of the duty finder will allow you to challenge duties with smaller parties. New duty roulette types/conditions. 
– New loot systems called “Lootmaster” and “All Greed” have been added for normal mode & hard mode raids. 
Also a digest of more info here 
Source: Final Fantasy Network