Not yet, sorry.
Postgres-R (8) is a prototype implementation of the original Postgres-R algorithm presented by Bettina Kemme.
This depends a lot on how you define 'complete'. But be prepared to think in months, not days.
We provide regular patches against current CVS code of Postgres on the download page. For your convenience, the source code is released under the same BSD license as Postgres itself.
Postgres-R is an effort to integrate a replication solution into Postgres. However, Postgres-R is currently a separate project for a good reason: it helps the developers to focus on their own code and makes clear who to blame for what. As soon as Postgres-R reaches production quality, the developers will discuss a possible integration into the core project again.
This is mainly a developers' decision and does not imply any disadvantage for the user. An all-inclusive Postgres-R package can be provided, no matter where exactly the Postgres-R source code lives.
See also these discussions:
Re: why is postgres-R not in standard dev Path. by Tom Lane
Re: Replication on the backend by Markus (Schiltknecht) Wanner
Just like Postgres itself, Postgres-R is written in C and tightly integrated into the core database system. Compilation can be enabled by the compile time option '--enable-replication'.
We believe that replication belongs into the database system itself due to its complexity. Especially for future extensions like data partitioning, parallel query execution and asynchronous operation, a tight integration with the database backend is crucial.