Google Maps API V3 pinch-to-zoom does not work with IE 11 on Windows 8.1 preview

Google Maps API V3 pinch-to-zoom does not work with IE 11 on Windows 8.1
preview

Trying to use pinch-to-zoom on multitouch screen with Windows 8.1 preview
and Internet Explorer 11 (IE later on) does not work with Google Maps API
V3 (none of the latest versions: 3.12, 3.13 and 3.14). The expected
behaviour is map zooming in and out.
The same feature is working just fine with Windows 8 and IE 10.
There seem to be two exceptions for the case:
https://maps.google.com
https://developers.google.com/maps/documentation/javascript/examples/map-simple
(any example being embedded in the docs pages; when viewed in a standalone
tab or window by pressing the view "full screen" pinch-to-zoom does not
work)
Does anyone know how that is achieved so that it could be used until the
issue is fixed?