ExpertFlyer flight alerts (a subscription) can be set to email you when a specified number of award seats in specific classes becomes available on a specific flight on a certain date. This is point to point, as in:
US 700 PHL-FRA 1 saver seat in coach 11/12/14
ExpertFlyer supports such award searches and alerts across several oneworld and AAdvantage partner airlines.
http://www.expertflyer.com/sessionlessClassList.do