I am really interested in this feature as well! I work as a concept artist and would like to be able to use all my favourite brushes from Photoshop in AP.
I just got the imac retina 5K and all of Adobes software is really slow on this computer. I put my faith in that AP will be my go to painting app, because it looks really, really promising. If it doesn't have all of the features Photoshop has, then I can live with that, but for me and I think a lot like me, it would be essential to be able to import abr brushes. From what I can see in the brushes options, it looks like it works very similar to how PS brushes are set up. I'm keeping my fingers crossed that this will be implemented!