It is true that nearly everyting seems to be spinning, but this doesnt mean that this spinning ever becomes infinite. A black hole does not spin infinitely fast, because the event horizon always has a finite and large extent where the outside observer 'sees' the total angular momentum locked up. Since nothing can move faster than the speed of light, the fastest a black hole can spin is determined by this limit, just as it is for everything else.

The most general black hole 'solution' is defined by exactly three physical parameters; Mass, Charge and Spin. An object collapsing into a black hole with non-zero spin, conserves its angular momentum during the collapse, and this causes the geometry of the resulting 'Kerr' black hole to have a very different shape than a non-rotating 'Schwarschild' black hole.

Now, the singularity that forms is not a mathematical point at the center, but becomes a Ring Singularity with a finite radius, and a 1-dimensional cross section. Inside the ring forms a new kind of space-time that some solutions suggest is traversable into another universe like a doorway. The enormous gravitational radiation flows present inside the event horizon, however, make this possibility very remote.

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