I have an app written in PHP that I am porting to Meteor. This question is really two parts:
1) Currently, my server forwards all email to a PHP script that parses out the response and inserts it into a database, allowing users to respond to message threads by emailing reply+someidentifier@myapp.com. What is the best way of accomplishing this now that I am using Meteor?
2) From a performance perspective, should I running this on the same server that is hosting my application. Is this scalable?
I didn't notice it but you're using procmail? I've never done this before but you could tell procmail to put its files into a folder that Meteor can access. Then use the fs npm module to parse through these every few minutes & put these into a collection using the server side js.
From there you could make the UI you want to use to reply/make threads, etc.