Hacker News Reader

Ah. If your target is people who aren't going to be reading docs, I don't think any DB is really preferable. :)

Any more details about the project, or is it under wraps?

It's basically a simple blogging platform, going to be released OSS.

Most devs know how to get MySQL running without too much thought, but many don't even know what Postgres is.

It might be worthwhile educating them. It shouldn't be that much harder to show them how to setup Postgres than MySQL :-)

If it's only a simple blogging platform, it might well be that MySQL will do the job just fine though.