They've made it
very,
abundantly,
clear what their end goal is, and to be honest they're probably the only company in existence right now with the capabilities of pulling this kind of vision off. They are really one of the few companies in it for the long haul with just their single universe, and everything they've done (including a few missteps here and there) has been to further that ultimate goal: One gigantic universe, the ultimate science fiction sandbox.
Even the now officially cancelled World of Darkness MMO gave them valuable tools in the furtherance of this goal with the development of the Carbon Character technology that is currently in use by the character avatars in EVE Online.
Incarna was a misstep, because they tried to do too much too fast. But it did give us actual avatars, and a place in station to walk around.
Dust 514 Was a huge leap for them, and primarily designed as a learning experience. It taught them about developing with third party software (Unreal 3), for a specific dedicated piece of hardware (PS3), and dealing with external systems outside their control (Microsoft refused to change how they do patches/server systems and as such it became a Sony exclusive by default. It also taught them how Sony does things. Both of which are valuable learning experiences).
Dust 514 also taught them how to build an FPS, and to what level they were capable of integrating into EVE Online given the above listed experiences.
Valkyrie is teaching them about emergent technologies and what state of the art VR is capable of. How they'll use it to integrate into EVE Online in the future is a fascinating prospect.
They've now got these three major separate pieces to their game(EVE Online, Dust 514, and Valkyrie). What do they need to do to combine them all into their ultimate goal of everyone being able to access any part of the universe? They have to tie it all together, and integrate these three massively different and mostly separate systems into one cohesive whole. Guess what's coming out soon? The easiest to accomplish next step: a single character avatar can access all three games.
Project Legion isn't going to be a PC Dust 514 port. It is going to be the next step into total integration with EVE. They want actual players fighting down the halls of starbases, they want actual characters exploring ancient ruins. They want pilots leaving their ships, and stepping into the depths of stations or dropping down onto a planet. They want to do things that just aren't feasible with the current iteration of Dust 514, or likely even Project Legion, but they couldn't create the next step without the knowledge gained from those before it.
tl:dr
CCP is stretching it's wings and finding out what is possible on current hardware and development styles and determining how they're going to be moving forward to achieve their goal of a single shared and fully integrated universe. The PS3 and VR systems are just stepping stones.