Isn't the Titan X also about RAM? It has 12GB to the GTX 1080's 8GB. At the low end you could just buy more than one GTX 1080, so it looks like a good deal there, but at the top end you are running out of slots for cards.
One thing not mentioned in this gaming-oriented press release is that the Pascal GPUs have additional support for really fast 32 bit (and do I recall 16 bit?) processing; this is almost certainly more appealing for machine learning folks.
On the VR side, the 1080 won't be a minimum required target for some time is my guess; the enthusiast market is still quite small. That said, it can't come too quickly; better rendering combined with butter-smooth rates has a visceral impact in VR which is not like on-screen improvements.