Earlier quoted context omitted.
Off the top of my head benefits: -No mental context switch when working on both ends -Easier serialization (though JSON is pretty portable...) -Sharing code They aren't exclusive to Node and JS, but browsers run JS and will continue to for the foreseeable future. Since the front end can't budge its language at the moment, the back end has to.
I see the "sharing code" claim a lot but I haven't really seen it substantiated. Seems like you write a few little functions but it's not like you sharing the same framework which would be the real benefit.
Seriously? A very common problem in web apps is validation logic is usually duplicated in JS and Server side language.
Node allows the same logic to be used in both cases. These are not a 'few little functions'. Validation is a central part of most business applications.
Given the potential to template html with javascript, and to code exclusively in javascript. You could end up with webapps written entirely in one language.
Whether that is a good thing or not remains to be seen, but it is something that we should pay attention to.