So far as anyone can tell, Missa in Cantu: A Seminar in the Sung Mass for Celebrants, October 17-19, 2007, in Chicago, in association with St. John Cantius Parish, is the largest training seminar in the sung Mass to take place in the postconciliar period in the US.
Most such seminars have, in the past, attracted 2-5 priests, on average. This has been sad since celebrants are rarely if ever trained in the sung Mass in seminary. It somehow hasn't been the thing, despite Vatican II's emphatic statement that a sung Mass is more noble than a purely spoken one. And earlier rubrics are very clear: the sung Mass is normative. The spoken Mass is supposed to be the exception to the rule.
In any case, this seminar seems to indicate a substantial change in outlook is taking place. It seems as if some 50 priests are coming, which is just splendid, so lift up your hearts. The seminar trains in both ordinary and extraordinary forms, so there is not one priest in this country who will not benefit from it.
The program director for CMAA informed me yesterday that there have been some cancellations in the meantime, so there is still room. Get your pastor there! Email your priest friends! This is going to be a wonderful seminar. If you have questions, email the director of programs.