Now I've read:
It’s a Mitzvah: U2 Reschedules Concert Because of Jets Game and Jewish Holiday
U2 would not seem to be the sort of band that takes Jewish holidays into account when preparing its touring schedule, but the coming observance of Yom Kippur has required the group to reschedule a show planned for Giants Stadium next month. In a news release on Thursday, publicists for U2 said that the group’s concert scheduled at the stadium in East Rutherford, N.J. for Sept. 25 has been moved to Sept. 23. The change was made after the New York Jets rescheduled their Sept. 27 football game against the Tennessee Titans to 1 p.m. from 4:15 pm to avoid a conflict with Yom Kippur, which starts at sundown that day...
"To shuckle" is to sway during prayer. It is an expression of devotion and those in prayer can be observed swaying back-and-forth, side-to-side, this all the while, during the Silent Prayer, keeping one's feet together for the duration of the 18 (19) Benedictions. Some have been seen to open their arms wide and sweeping them about (thus occasionally hitting the people standing next to them or even knocking some over, this even before the Tachanun prayer), or even jumping in place.
The Yam Shel Shelomo (Rabbi Shlomo Luria of Lublin, 1510-1573) writes that he observed people jumping and dancing during Kedusha, and he calls this practice a "Minhag Burim" ("the custom of fools").
The Talmud records, however, in another context this behavior:
It has been taught: Such was the custom of R. Akiba; when he prayed with the congregation, he used to cut it short and finish in order not to inconvenience the congregation, but when he prayed by himself, a man would leave him in one corner and find him later in another, on account of his many genuflexions and prostrations.
So, for those Jews going to the concert, shuckle away!