I have been killing myself with Postgresql 9.1, pgpool, and heartbeat Chef configuration management and have pretty much hit a wall. The current situation has to do with idempotent and when I manually remove the postgresql-9.1 package with a apt-get purge postgresql-9.1 is happily does its job. The problem is when I run chef again I expect it to install the package again but it does not. The more Chef you use the more you will learn to love and hate it. FYI the Coroutine team has done some of the work for you on postgresql replication in chef if you need that kind of stuff.
Not very useful stuff today, but I have been starting to look at private chef and might have some post coming about that soon.
Good luck out there, and if you looking at this you might also be interested in working at Rdio Senior-systems/Operations-engineer