The fact that there is a full-stack version available doesn't mitigate the fact that the multitudes of custom stacks out there are going to mean two bad things:

The fact that there is a full-stack version available doesn't mitigate the fact that the multitudes of custom stacks out there are going to mean two bad things: 1. The default full stack will be a lot less thoroughly documented, tested and debugged because a lot fewer people are using it. 2. The chances that I can just jump in and start hacking productively on somebody else's Merb app are slim because it's likely I'm not familiar with some of the components you're using. I still don't understand at all why I'd want to use Merb. What problem are you trying to solve here? Being slightly better than Rails in a few respects isn't even close to good enough to compensate for the lack of documentation, code maturity, available programming expertise, public success stories etc that Rails has going for it.