June 16 they will be announced. June 24 availability date.
What we know is mostly rumors. There will be R9 300 series cards. And mostly the top end ones. However, it is rumored that these will be tweaked R9 200 series re-badges. In other words, take a R9 290X, turn up the clock speed a little, increase the memory to 8GB, and rename it to R9 390X. Or some thing close to this.
What will be new is the AMD Radeon Fury flagship card, similar to what Nvidia has done with the Titan series. AMD is claiming that it will be the worlds fastest video card. This card is expected to be announced and released on the same schedule as the rest of the cards.
So just 10 more days till the announcements. Be patient.