What I really like about college basketball is that you can see teams progress up the rankings, then back down again if other teams figure out what their weaknesses are. Right now, IU is responding to the game plans of other teams; when they try to shut them down in the paint, they are able to shoot their way past them.
However, I doubt it will last because opposing teams are going to figure out ways to defend them, to lock out the big men, defend the three, exploit weaknesses, make IU come up with new ways to win. That's the nature of it and whether IU can sustain their success and respond to the changes other teams will throw at them remains to be seen.
From a fan perspective, I'm tickled to see them doing so well. I would have never thought they'd be this far, so fast. If they falter, it won't surprise me, but so far all the surprises have been fun to watch.