The boy just bought himself a spesh enduro (M5?) 2012 model. It's not really XC, he's keeping the hardtail for that, but it's proper lush and comes in at around 13 kilos wth a dropper post. It's an awful lot of "do it all" bike for the space it takes up.
Downsides? - too heavy for xc racing (although it's light enough for general xc riding and eats the downhill sections for lunch), elixir brakes are a fucker to maintain, 26" boots are getting harder to find.