Last week Dave Page announced that the next major release of Postgres will be numbered 9.0, rather than 8.5 as previous expected. This change was made because the next major PostgreSQL release will include built-in log-streaming replication, and that has always been considered a feature worthy of increasing the first version number.
While Postgres has had log-based replication support for a few releases, the 9.0 release will allow logs to be streamed to the slave using network transfer, which greatly increases the frequency at which logs can reasonably be sent. It also allows the slave server to accept read-only queries (hot standby), again a major feature addition.
Postgres 9.0 Coming
