I am also interested in it. I believe I've read there's a way. Something about an EasySounds Motif production guide issue. Maybe March, 2015? And some steps there.

YES - I also would buy the CS80 library...but wasn't willing to buy a white XF!

Isn't the CS80 library part of the Sonic Reality Yamaha Vintage Analog collection?
I bought this several months ago when they had a special on.
The Yamaha Music Production Guide 03/2015 has the VP1 sound library available.

Is this an option!
I've yet to see an answer...

The CS80 Sample Voice Library that is apart of the 40th Anniversary Premium Contents Pack (by Dr. Peter Jung) and the CS80 Samples that are apart of the Vintage Collection from the Sonic Reality (also included in the Premium Contents Pack) _ are cleared for use in this special promotion. I have no information on what will happen to this content once the promotion is over. Currently, they are both included in this promotional endeavor. I cannot, with any authority, even tell you what each subsidiary around the world is doing with the data, how it is being distributed and what will happen in the future.

In the USA (where YamahaSynth.com is located) the small print reads: Offer valid on the White MOTIF XF between August 1, 2014 – July 31, 2015, offer valid on the Black MOTIF XF between Jan 1, 2015 – July 31, 2015.

Obviously, the data has value and will in all likelihood will be made available for purchase at some time in the future or become apart of some other promotion (it's impossible to say). I will attempt to find out what the plan is, but I cannot make any promises. And mileage may and probably will vary in different parts of the world.

Thank you all for your interest, I will find out what I can and report what I find out.