There are several new things and lot of information is being shared during Directions NA. Unfortunately I was not there but the community was so active sharing the news through twitter posts /blogs which really helps people who did not attend. Thank you everyone for sharing the information.
One thing they announced was Dynamics 365 Business Central Road Map. As you can see it clearly shows by 2020 the only client available would be Web Client and the Programming language is AL. Although, I am not sure how this will end up by 2020 but based upon the progress we have made in last couple of years it is quite possible.
Although we still be using CAL / RTC client on older versions this will fade away as people upgrade or try to take the advantage of SAAS version of Business Central. There are lot of improvement being made every month with AL, whether it is adding more events to subscribe or new functionality to make it available.
You can also become a contributor to the AL on GitHub for more information please check the following link