I rarely seen any RoR clone took off. I don't mean to talk bad about them, but I'd be worried about the community and momentum behind them. I wouldn't want to use a niche technology to find out that I might have to extend or take ownership myself down the road when their leader decided to resign to pursue something else because they find their work no longer rewarding nor interesting (well, to begin with, they're cloning a popular framework instead of coming up with original ideas or being a visionary).

SharpArchitecture, while swell and neat, doesn't scratch the itch of "this stuff really isn't that hard". There's a metric s* ton of concepts and code in there that are more suitable for a military defense system, let alone a startup.