I haven't tried Mongo.db, but Node.js takes up a lot of resources in a browser, Node.js apps feels a bit like the widest book strategy in the bookstore, you have to shove other stuff out of your browser, in order to use stuff that uses Node.js, and I feel that as a rather arrogant approach to deliver software, especially, when the functionality of Node.js apps doesn't really dictate the necessity.

AS for Javscript, there are worser languages out there, and the debuggers are good enough now, so it can be perceived as a "normal" language.