As some of you know, we're building our new startup on top of Merb. One of my favorite things about Merb is how much easier it is to understand than Rails is when you need to hack on something that's outside the realm of what the framework expects you to use it for. I think that Ezra Zygmuntowicz put it best in his recent tech talk on Merb:
A lot of people tend to end up treating Rails as a blackbox because it is eighty thousand or so lines of code and it's a little bit hard to step into and figure out what's going on because there's so much advanced Ruby meta-programming going on inside of there. I kind of feel like the place for meta-programming and that kind of stuff is in your own application code. I'd rather have the foundation that you're building on top of be as simple and as easy to understand as possible so that when you do hit the wall and you need to look inside the framework you don't get grossed out and you can get in there and actually do stuff with it.