I know the official rulings aren't out yet, but does Reprieve from Tales of Middleearth counter the spell it returns?
No.
Reprieve does exactly what it says it does: It puts the targeted spell back into its owner's hand from the stack. That's all.
If it countered the spell, it would have the same template as Remand, which it doesn't. The fundamental difference between the two is that Reprieve can affect uncounterable spells and won't trigger things like Baral that care about spells being countered.
Disclaimer: This answer is correct under the rules at time of posting, but concerns a card from an upcoming set. The rules may change when that set releases and invalidate this answer. (I severely doubt it in this case, however.)









