After last updates on www.windowsondevices.com site (microsoft started to ship free development kits) it looks they moved forward launching silently the arduino SDK on nugget
Official C++ Galileo SDK:
NuGet Gallery | Galileo C++ SDK 1.0.0
P.S. You can also get the 188.8.131.52 and 184.108.40.206 versions that were hidden by Microsoft but still available on nugget (I think they are development versions).
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