Heroku Changelog Slow query reporting to logs has been increased to 2 seconds for Postgres 9.2

Change effective on 02 May 2013

For all Postgres v9.2+ databases, the threshold for slow queries to be logged to Logplex is now 2 seconds. Previously, this threshold was 50ms.

Postgres v9.1 and below databases are not affected and will still classify queries taking longer than 50ms as slow.