FAA glider rating valid in Europe
 

Is an FAA glider rating (PPL w/ glider class rating) valid in Europe out of the box, w/o validation?

Out of curiosity, how about Namibia and Australia?

I can't comment about Europe, but here in New Zealand we recognise the FAA PPL/G as a direct equivilent of our QGP (Qualified Glider Pilot). Certainly if you turn up at our club with your PPL/G and want to take our club aircraft up, all we would require is a local briefing, a check flight and a look at your log book. If you are also a member of an affiliated club then you would get club rates rather than public rates for hiring the aircraft.

Nice, that's the way I thought this should be. One more reason to visit New Zealand! :)

Germany as well (quite a surprise actually)
 

You could fly in Germany as well, provided you have a current medical and over 30 hrs of glider time - some rule interpretation from the 90's from the LBA, which still strikes me as odd if you look at how tightly they regulated anything else.

US-PPL, Fliegen mit US-Segelfluglizenz in Deutschland

Has not changed yet with EASA rules, yet, I believe...

In Australia we are similar to New Zealand.
You would need to join Gliding Federation of Australia as a short term member to cover various insurances. Local procedures would be a brief and check ride.
I have flown in Europe using my FAA license, Germany and Hungary OK.:ok:
In France you need to get license validated in advance but not so difficult.