Based on what? Heard news on Sky that someone had died riding one - that happens on many modes of transport. I think the battery melting is more worrying.
Please read the article: "Following a rash of explosions and house fires connected to hoverboards".
PS: it is interesting that you have just created this HN account to ask this question.
What for this, worried as my little girl wanted one for xmas so it caught my eye. She is getting an Anki OverDrive instead :)