In the US it could be possible for the Xbone to lead, but in Europe i just do not see it happening.
Xbone might get a good hold in the UK, but Mainland Europe is Sony land through and through, with some PC gaming here and there.
we are already seeing the trend in the current sales numbers, the PS4 is beating the Xbone week after week in Europe with numbers almost 3x higher than Xbones.
EDIT: another thing to add is that a lot of the services provided with the Xbone are Exclusive to the US, and if they ever come to Europe it won't be everywhere at once(probably UK first).
there is just no reason to own one in Europe(IMO) and i don't see any reason to own one in the near future.