I reckon that they will all think that Snape has gone over to the dark side, but in reality, he won't, he'll just be spying or something like that, because ther eis always this thing going on where Harry Ron and Hermoine you know, like wonder as to wether or not he's the bad guy, but he never turns out to be...
Urhhh, i think that I'm rambling again... I know what I mean! Really I do! *don't think that anyone else does though!*
I think that it will be someone close to harry, even if it's not ron, and they will be a 'good' person... and they will like hand over valuible info, realise what they have done, then rush back to the light!!!
who knows really!