3 each day. 2013 start times were 5:30, 6:45 and 8:00 PM. All concerts I've seen lasted 30 minutes. Some artists play the same set and others mix it up between the 3 showings.

the line up:
-- September 19-21 -- Jo Dee Messina
-- September 22-23 -- The Pointer Sisters
-- September 24-25 -- Rick Springfield
-- September 26-27 -- Christopher Cross
-- September 28-29 -- Hanson
-- September 30-October 2 -- Air Supply
-- October 3-5 -- STARSHIP starring Mickey Thomas
-- October 6-8 -- Sugar Ray
-- October 9-10 -- Fuel
-- October 11-12 -- Sister Hazel
-- October 13-14 -- TBD
-- October 15-16 -- Billy Ocean
-- October 17-19 -- Night Ranger
-- October 20-22 -- Smash Mouth
-- October 23-24 -- Jim Brickman
-- October 25-26 -- Los Lonely Boys
-- October 27-28 -- Wilson Phillips
-- October 29-31 -- Dennis DeYoung, original member of STYX
-- November 1-2 -- 38 Special
-- November 3-5 -- Boyz II Men
-- November 6-7 -- David Cook
-- November 8-10 -- Big Bad Voodoo Daddy
we try to see at least one set of each entertainer that is there while we are.
weekdays are usually less crowded, but in many, many shows, we not once seen no seats available, even on fri/sat/sun nights.
if you want to sit right up front, you'll need to get there hours early to queue (yes, there are groupies

)...else, in our experience, there is some seating and lots of standing room even after the concerts start.