Perhaps it is a simple dose of reality that is slowing down (if that is, indeed, what's happening) the rush to canonize Pope John Paul II. Certainly a pontificate a quarter century long would produce a great deal to investigate. According to reports from Catholicculture.org , and NCRonline  the immediate cause of the slowdown is the revelation of extensive correspondence with Wanda Poltawska, described as a long-time friend and adviser to the pope.
Reports Catholicculture.org: "Pope John Paul II's closest aide is strongly criticizing Dr. Wanda Poltawska over her decision to publish five decades' worth of private correspondence with the late Pontiff. Cardinal Stanislaw Dziwisz of Krakow says that Dr. Poltawska -- a psychiatrist and concentration camp survivor-- is claiming "a special relationship where none existed" and that many others corresponded privately with Pope John Paul.
Fr. Adam Boniecki, former editor of the Polish edition of L'Osservatore Romano, countered that Pope John Paul and Dr. Poltawska had a strong relationship, like that of a brother and sister -- akin to that of St. Francis de Sales and St. Jane Francis de Chantal."
Equally intriguing is the apparent reluctance, according to the report, of Cardinal Angelo Sodano, the longtime Vatican secretary of state and Cardinal Leonardo Sandri, Sodano's top deputy for seven years, until 2007, to testify in the effort. Sandri met regularly with the late pope.
What hasn't been raised as a problem is John Paul's friendship with the late Fr. Marciel Maciel, founder of the Legionaries of Christ, a conservative and secretive religious order. Maciel was disciplined after more than a dozen former priests and seminarians alleged that he had sexually abused them as youngsters. It was revealed more recently, and after he died, that he had had a mistress and fathered at least one child.
John Paul often praised Maciel, once calling him "an efficacious guide for youth," an awful and tragic misreading of reality. The pope largely ignored the claims of the alleged victims; an investigation of Maciel was stopped abruptly during the last years of his reign.
Sodano, it is known, was a good friend and outspoken defender of Maciel until the Congregation for the Doctrine of the Faith completed its investigation and Pope Benedict XVI issued his discipline of Maciel. Sodano was one of the cardinals who got to see the accumulated evidence against Maciel during a meeting of the cardinal members of the CDF in 2006.
Does what Sodano learned about Maciel figure into his reluctance to testify on behalf of John Paul II? Is that area being investigated at all?