PostgreSQL may not be better on all possible points of comparison.

PostgreSQL replcation alone isn't comparable to MySQL with Galera. I don't know enough about the various extensions to PostgreSQL to know which ones could give you

* Synchronous replication * Active-active multi-master topology * Read and write to any cluster node * Automatic membership control, failed nodes drop from the cluster * Automatic node joining * True parallel replication, on row level * Direct client connections

in a reliable and perfomant manner. Keep in mind I'm just atarting to play with Galera, I haven't used it in production yet, but it's making my planned architecure much simpler to manage than the traditional MySQL or PostgreSQL replication approaches.