Hi everyone, just fyi - I went for their public tour today. It was their first session, at 10am. The group comprised of 15 people. Meeting point is the West entrance and we started the tour at the Sports Museum and Hall of Fame. Then we moved on to the grandstand, and the private VIP lounge. After that, along the outside of the stadium to the East entrance, where we climbed the stairs to view the cauldron, floodlights, and scoreboard. Following that, a tour of the Sports Medicine Centre (a few of their facilities and a chance to meet any national athletes that are there), Kallang Athelete's Training Room (very 70s-looking gymnasium), walk along the old locker rooms, and another exhibition on the stadium at the end.
Entire tour takes about 2 hours. Photography is allowed throughout the tour, and they give you about 5 to 10 mins free-and-easy time at each stop to take pictures, or explore on your own. Best to go on a good weather day, because the tour won't include the floodlights and cauldron if it rains.