The Destiny 1 exotics should all go forward into Destiny 2. However, you should only be able to use them if you owned them in Destiny 1. That's a cool way to connect the games between each other. By no means do I expect legendary items to be shared or stay the same. Speaking of Destiny 2, it should have its own massive set of new exotics, so newer players shouldn't feel too bad. If anything this will keep Destiny 1 alive even after 2 comes out, for hardcore collectors.