In theory you should use the right tool for the job and there shouldn't even be a discussion. However in reality not all DB's are created equally. It comes dow

In theory you should use the right tool for the job and there shouldn't even be a discussion. However in reality not all DB's are created equally. It comes down to this: do you want to spend a known amount of time hammering in a screw, or do you want to spend an unknown amount of time optimizing your state of the art, but unproven screwdriver. This is important for people starting a business. You don't start a business to test out new technology, that's what weekend projects are for. They need to be focusing on the product and not spending time 'just getting it to work'. Mysql/MC aren't sexy, but it takes a trivial amount of time to set up and tune them. There are lots of caveats to this; the entire argument can be nit-picked to death. But I think it holds for the generic webapp template that just needs data to persist and then be served back to users.