It's not surprising at all that insiders have taken advantage of their privileged access to information in order to raise a few bob through online betting.
They only got caught (well suspected as no charges have been pressed) because a betting site got suspicious. I doubt there are audit trails in places that would spot any cheating on the outcome of the result etc. I've noticed that on programmes like Strictly Come Dancing they don't tell us who got how many votes – it's all left rather woolly.
BT is quoted in the Register piece as saying:
However, one thing we would like to make clear is that this does not affect the integrity of the result. It is impossible to tamper with the results to affect the outcome in anyway – the viewers' choice will win.
I chortled heartily at that. Impossible to tamper? I don't think so BT but I understand why you're saying it. They're just one byte away from being totally discredited and the game show voting is proving much more profitable than the UK's e-voting pilots ever were.