According to T-Mobile, the Sensation 4G update will address software stability, improve the phone's battery life, improve the Trace dictionary; resolve screen unresponsiveness, screen shot features, lock screen, and icon pixilation; improve its WiFi connectivity and fix the green line on photo issue. The update should already be rolling out to Sensation 4G users by now, but in the event you haven't received your update yet, you can manually check for it by going to Menu > About Phone > HTC Software updates > Check.
As usual, backup your device before attempting any updates and let us know how it goes for you.
