Feeling weirdly guilty about it, though I'm pretty sure that selling 260quid items for 60 is not going to make Jeff Bezos any richer. Also, yay! new kayak!? Wait and see, I guess.
... and they finally noticed the pricing error, and cancelled the delivery at 2:30pm today. The kayak is now listed at £329, which puts it well out of impulse buy territory. Drat. Oh well, I expected it really!