Rod1022

Out of interest, when saying the 1080 will be "20-25% faster than the 980 Ti" you're talking about a reference 980 Ti, right? If so, it's worth noting that the non-reference 980 Ti cards are sometimes quite a lot faster than reference cards. I'm not in the market right now but I'm looking forward to seeing the real numbers with some good benchmarks. I've seen people selling their 980 Ti cards for crazy low prices to get the money for a 1080. I hope the 1080 is an awesome improvement for the sake of new buyers and people who've waited but pre-release hype is often much different to real-world numbers so I'd personally not gamble on something like that until you've seen the benchmarks.
 
In your case, OP, you have neither right now so I think it makes the most sense to wait for a 1080. It sounds like you just got a great monitor so you might as well wait a little and get the better of the two cards. Have fun. 

Wait for the 1080. Practice some patience, it'll help you in more ways than GPUs.

they werent focusing only on vr, however they did say the performance of a titanx on vr is insignificant compared to the GTX1080
they also added native DX12 support which will trump over the 980ti (async-compute wise if they did even implement it, in any rate it will be better)
they also mentioned that its about x1.6 faster than a 980 in the witcher 3, however take it with a grain of salt because its from their site

Sure, but in this case it does matter. At least to a certain degree. The OP isn't comparing a stock with a stock or an OC with an OC; he/she is considering a highly-overclocked Ti with a stock 1080. Sure, the 1080 might be 25% faster than the 980 Ti but a 1080 might not be anywhere near 25% faster than the Strix card mentioned (but maybe it's more than 25% faster, which would be awesome). We don't know yet.

If you don't need 144Hz super high refresh rate, then yes.

The X99 platform is aligned more with workstations for rendering and heavy computation whereas the Z97 platform is good for overclocking and you can throw gaming in there too. In terms of bang for your buck for just a gaming rig, there is no reason to spend the extra money on X99 - you are much better off putting the cash into a better GPU.
 
And if you are turning your nose up at an "old" generation then look at Z170/Skylake/DDR4

Definitely Acer, my wife has hers for about a week and it's noticeably better than my 34" LG.  Less backlight bleed and super smooth with her 290x.