Wi-Fi Aware provides an efficient mechanism for always-on service discovery, whereas Wi-Fi Direct provides data connectivity among groups of devices. The technologies are complementary. Once an interesting service is discovered, a device can initiate a high-performance connection using Wi-Fi Direct for data transfer related to the service, e.g. sharing photos or playing a multiplayer game.
Wi-Fi Direct has the big limitation that one's device is usually already connected to an AP. It's easy to route traffic to other devices over the LAN or WAN than to set up a separate direct link. It will be interesting to see if Wi-Fi Aware drives better usage of Wi-Fi Direct.
The other option is for devices to have two antenna, which I would consider more useful (battery permitting, eg for laptops). That's the way mesh networks seem to be going, often with the one antenna at 2.4 and the other at 5GHz.