Good news for people who lead busy lives: it won't take you hundreds of hours to reach the centre of the galaxy in No Man's Sky, as the person who purchased a pre-release copy for $1,300 achieved it in some 30 hours instead. Sean Murray had said in previous interviews that you could expect to be playing the game a long, long time to reach its "end goal", but without spoiling too much, there's apparently a resource that you can collect which shortens the campaign length.
Not that 30 hours is short to begin with – and let's keep in mind that it all depends on how much you intend to explore. The leaker, writing on Reddit, says that he took his time with the game – but admits that he still has plenty of things to do. We're not going to quote his posts because there are spoilers within, but he points out that there's very, very little repetition in the planets, and that the sound design is some of the best that he's ever experienced.
That said, he does have some complaints – namely the pacing of the experience and bugs. It's worth remembering, of course, that the leaker is playing on pre-patched code; Hello Games has already said that it's working on a day one update for the title, which is yet to be deployed. You can read more of what he has to say about the game through here, but do so at your own risk – there's just over a week to go now until this is released, after all.