Hello,
in general my advice would be to stick with native features, therefore
use either Streaming Replication (or alternatively log shipping
replication). You might need some tools to help you manage the cluster,
clients routing and balancing but I suggest you look into this later.
On Thu,
I am doing POC on Posgtresql replication. I am using latest version of
postgresql i.e. 9.1. There are multiple replication solutions avaliable in
the market (PGCluster, Pgpool-II, Slony-I). Postgresql also provide
in-built replication solutions (Streaming replication, Warm Standby and hot
standby).