What should I put in a meteor .gitignore file?

Your gitignore should also contain:

public/node_modules

And you supplement this with a properly crafted package.json that manages node module dependency installation.

This will necessitate a npm install when installed somewhere new.

The only directory you want excluded from version control is .meteor/local.

Meteor automatically creates the right .meteor and .meteor/.gitignore, though -- you shouldn't need to do anything.

You might want to put any configuration settings files in there if you are pushing to a public repos.

I store any security sensitive data configuration settings like encryption keys and various passwords for services like smtp, twitter, facebook and others in a config.js and then put that in .gitignore or in the info/exclude file. Stuff I don't want in a public repo.

Just an additional suggestion to consider for your .gitignore