ServiceStack/ServiceStack.OrmLite — pull request #34 by stefantarrant (2012-03-06 15:19:31+00:00)
Title: Changed column definition for strings to text from VARCHAR.

From PostgreSQL documentation:
Tip: There is no performance difference among these three types (variable-length with limit, fixed-length -blank padded, variable unlimited length), apart from increased storage space when using the blank-padded type, and a few extra CPU cycles to check the length when storing into a length-constrained column. While character(n) has performance advantages in some other database systems, there is no such advantage in PostgreSQL; in fact character(n) is usually the slowest of the three because of its additional storage costs. In most situations text or character varying should be used instead.