This is exactly how I feel. I am currently working on a project for a client where they expect to have about 3,000 users each with some basic profile informati

This is exactly how I feel. I am currently working on a project for a client where they expect to have about 3,000 users each with some basic profile information, and the ability to upload some documents etc - nothing too crazy. I don't think they ever have to worry about scaling to 50,000 users and performing any data-intensive database queries. Why not use something like Mongo in this situation?