St. Louis Catholics  – well, many of them – will be saddened to know that Archbishop Burke is leaving them. As rumored, he has been named Prefect of the  Supreme Tribunal of Apostolic Signatura.
More from John Allen:

The appointment puts Burke, who turns 60 on June 30, in line to become a cardinal.
Burke is expected to relocate to Rome in August to take up his new duties.
The nomination comes as little surprise to church-watchers, who have long speculated that Burke might return to Rome at some point. Burke received a doctorate in canon law from Rome’s Gregorian University in 1984, and from 1989 to 1994 he served as the Defender of the Bond in the Apostolic Signatura, a position equivalent to the top defense attorney in the Vatican’s legal system.
In July 2006, Benedict XVI named Burke a member of the Apostolic Signatura, a move that some observers at the time interpreted as grooming him to eventually take over the top spot on the court.
In the Vatican, there are three courts: the Roman Rota, which is an appeals court that deals largely with cases involving requests for annulment of a marriage; the Apostolic Signatura, more or less the “Supreme Court” of the church; and the Apostolic Penitentiary, which handles cases involving the “internal forum,” meaning especially delicate matters that can’t be resolved through the normal legal process.
In Catholic circles, Burke has long been considered one of the most precise legal minds at the senior levels of the church, with an encyclopedic knowledge of the Code of Canon Law, the legal system of the Catholic church, as well as the tradition of case law stemming from that code.
snip
Generally speaking, the following sorts of cases are heard by the Signatura:
• Conflicts between two Vatican offices;
• Appeals against decisions by diocesan bishops and Vatican offices;
• Appeals against decisions by the Roman Rota.
Two other Americans are members of the Apostolic Signatura: Cardinal Edward Egan of New Yor, and Bishop Thomas Doran of Rockford, Illinois.

But..not before placing a St. Louis nun, Sr. Louise Lears, under canonical discipline:
(In the Archdiocese’s typically excellent mode of communication, all the pertinent documents are linked at the top of the page)

After a canonical process of several months, Archbishop Raymond Burke has, today, decided the case of Sister Louise Lears, S.C., a member of the “pastoral team” at Saint Cronan Parish, who was accused of four delicts, all connected with her encouragement of, promotion of and participation in the attempted ordination of two women to the Sacred Priesthood at a local synagogue in November of last year. Delicts, which must be published in the Church, are grave and external violations against the Catholic faith or moral teaching. A list of several delicts is found from cann. 1364 to 1399 of the Code of Canon Law.
The delicts of which Sister Louise Lears is accused are: 1) the obstinate rejection, after written
admonition, of the truth of the faith that it is impossible for a woman to receive ordination to the Sacred Priesthood (cann.750, §2; and 1371, 1º); 2) the public incitement of the faithful to animosity or hatred toward the Apostolic See or an Ordinary because of an act of ecclesiastical power or ministry (can. 1373); 3) the grave external violation of Divine or Canon Law, with the urgent need to present and repair the scandal involved (can. 1399); and 4) prohibited participation in sacred rites (can. 1365).
 Throughout the canonical process, Sister Louise Lears and her canonical advocate have been given ample opportunity to review all of the proofs and arguments in the case, and to respond to them. In other words, Sister Louise Lears’ right to defend herself against the accusations was carefully safeguarded.

You’ll find good coverage and commentary on both matters at the  St. Louis Catholic blog.