Does this type of clustering automatically provide for fault tolerance or better availability?
Yes and No. This kind of setup just provides an automated way to make configuration identical across the instances. For stateless (no state on the server) and state-safe (state saved in a persistent store) applications, this is sufficient (in conjunction with a hardware load balancer or web cache as a front-end). However such a setup is not sufficient for stateful application failover, and islands have to be defined. For more information on this, please see the Oracle9iAS documentation.
