Alright, so Peace Talks seems like a pretty standard card, but this question came up in a forum I frequent, and I don't know the answer. Here is the situation.

Alex casts Lightning Bolt targeting Naomi
In response, Naomi casts Quicken, then when Quicken resolves, she casts Peace Talks
Does Lightning Bolt resolve?

The original wording of Peace Talks says that players can't play spells or abilities that target, which suggests that spells previously cast would still resolve. But the Oracle text of Peace Talks says that “players and permanents can't be the targets of spells or activated abilities”, which sounds more like shroud, which would mean Lightning Bolt has an illegal target and would be countered when it tries to resolve. Which of these is the correct option, and is the new wording a functional change to the original wording?

Lightning bolt is countered since its only target has become illegal by the time it tries to resolve.

The printed wording doesn't work under current rules. “You can't cast X” works only in the zone the card would be cast from, that is, the ability has to exist before the spell is put onto the stack and will act before the spell has been put onto the stack. However, choosing targets happens only later; so the ability has no way of knowing that the spell will target players or creatures and thus can't stop it in time. That's why this kind of effect can only be based on intrinsic characteristics of spells (e.g. Meddling Mage's effect is based on the name of the spell, which we know before it's cast).

Daniel Kitachewsky
L3, Paris, France
Rules NetRep