Has anyone ever out-guessed JKR?

[ladyramkin2000]

No: HPFGUIDX 102592

I was thinking about Kneasy's brilliant suggestion that someone 
(almost certainly Ron) is going to be imperio-ed in Book 6 or 7 and 
wondering idly what would be JKR's reaction if she read it and he was 
right(ranging from "I don't suppose anyone will notice" to "Bugger, 
now I'll have to re-write whole chunks") From there, I began to 
wonder if anyone on any of the HP groups has ever come up with a 
prediction that turned out to be right - REALLY right.  Surely among 
the host of theories, sane and insane, someone must have come up with 
something that proved to be spot on. I would be fascinated to know if 
anyone can make such a claim.

Sylvia