I knew Daley personally and worked with him during last year's TT.
I spent 3 weeks at the TT last year working on the University of Nottingham Electric Superbike, and it's quite hard to grasp the mentality of the TT riders sometimes. Most are there without being paid and just want the glory, and are fully aware that they're either bringing their bikes home or die trying. I honestly don't know how they do it, I felt quite nervous everytime Daley went out on our bike, and they're so relaxed about it.
Daley was such a figure and great rider, he will be truly missed. The organisers at the IoM TT try their best to hide details from the media/public, but word away spreads in the Paddock, and from what I've heard, it's very likely he crashed because of a mechanical failure.