>i'd bet a weeks pay that the vast majority of youtube views (especially after exluding viral content) come through the youtube recommendation system and not external hyperlinks.

I'd take that bet. There's a lot the agorithm does, but there's also a lot of companies and people sharing links to the videos. Any new movie trailer or album drop would definitely be linked from twitter or some company homepage. And I wager those are what make up the most views.

But I wouldn't be surprised to be right or wrong on this. the recommendations certainly aren't a tiny portion.