The information out there isn't exactly clear on where the tips that led to bin-Laden's death came from, but some reports, including the New York Times, mention that detainees at Guantanamo Bay provided the identity of the courier, pushing over the first domino leading to the events of May 1st. The Atlantic asks if this one "victory" make some of the aspects of the war of terror that made us uncomfortable acceptable in retrospect:
Given Hosenball's notes, separated by a few paragraphs in his piece, that "veterans of the Bush administration [have been] quick to claim credit for the torture-like techniques," while "Obama Administration officials confirmed the sequence of events—U.S. intelligence did not learn the identity of the courier until after the CIA interrogation program was terminated," it seems likely there could be some spin even in information from anonymous sources; the obvious issue with anonymous sources, for the reader, is that you don't know who they are or what agenda they might have. That said, it certainly looks like both sides face hurdles in maintaining their positions: waterboarding supporters have to deal with the fact that the crucial information leading to bin Laden's location came after the waterboarding stopped. Anti-Guantanamo activists have to deal with the fact that such quality information came from illegal detention centers, including Guantanamo.
Andrew Sullivan also addressed whether credit must be given to waterboarding, eventually finding that we should instead recognize:
Old-fashioned, painstaking, labor-intensive intelligence work. The American way. We never needed to stoop to bin Laden's standards to get bin Laden. We needed merely to follow our long-tested humane procedures.