From Blizzard’s official announce:

There has been some confusion in regards to whether or not the act of “rooftop camping”, or killing players while using geometry to avoid the town guards, is allowed. We will no longer condone this act in game. Players who participate in this method of PvP will be given a warning and educated on this new policy, and further action will be taken as circumstances warrant. We wish to provide a fair playing field to our customers, and this abuse of game mechanics has been hampering that effort.

Firstly a precisation: there’s absolutely NO confusion. It’s Blizzard to be confused. The “Rooftop Camping” in PvP has been exploited by the players since release and when this problem was brought up Blizzard answered officially that the axction was allowed and didn’t consist in an exploit. Then, about a week or so ago, someone spotted a sticked post on the european forums stating that the “rooftop camping” was instead considered an exploit and so not tolerated. Today they “agreed” about extending the rule even to the american version.

Secondly: this is a long overdue good decision. But what about making the rules work instead of threaten the players?

Is it so hard to flag those buildings so that players won’t be able to run on top of them and teach at the same time the guards to deal with them? (for example by giving them an effective boomstick)

Fix the exploits, do not just threaten for them (and if we consider the beta it’s more than six month that this exploit is left untouched).