We were up there Sunday, the day after Daniel B. Camped at 6500', left camp 5:30 AM. Reached the summit block just before the sun hit the snow in the gully, about 8:30. Good cramponing most of the way up the gulley, with 2 scramble sections where it was melted out, belayed 1 of those. We were the first of 3 groups, so didn't have to deal with the bottleneck horrorshow (but I have seen it up there). Snow softened quickly, good plunge-stepping on the way down. We did 3 raps, 1 double off the summit block, 1 single through one of the rock sections, and another double to the base, all with 30m ropes. Back at camp at 2:30.
Navigation on the way off Shannon Ridge was tricky, as Daniel B noted. We started out too far skier's right, used our GPS track from the day before to get back on route. We saw what appeared to be several flagging lines, didn't trust them.
Water: the route is definately in... go get it.