From the start of 2012, the PSA and WISPA World Tours - along with WSF World Championships - are mandating that referee decision cards and electronic consoles are used at major events, rather than hand signals.
The events covered initially will be PSA World Series, WISPA World Series & Gold, and all WSF World Championships. While there will be exceptions - where it is discretionary rather than mandatory, as notified, e.g. qualification rounds - the joint intention is that the use of hand signals used by the three referees to communicate their decisions will be entirely replaced by the standard size/colour four-spoke referee decision cards and approved electronic systems.
The cards prevent players seeing the decision of individual referees, while the electronic console adds a new dimension to both the decision and its display for spectator and broadcast audiences on all-glass show courts.