Nothing about Enduro is new.
There has been Enduro races in Europe for years, even here in the UK there was the “Kona Mash-Up” at Afan in 2007 / 2008 – the format was simple – you had to ride the whole course, but you only got timed on the fast / fun bits.
It’s a race format of the type of riding lots of people have been doing since the dawn of MTBing – namely plodding up a great big hill chatting to your mates, then giving it some helmet on the way back down again.
There have also been ‘big trail bikes’ for many years.
The only New, new thing I’ve witnessed about the ‘new’ Enduro thing is wearing goggles with XC lids, odd one that – but mostly I think a lot of the hype is coming from the World Enduro Series.