I tried Julia recently and am very excited about it as well, especially with the addition of DataFrames. The only thing that worries me is the disorganized nature of the Base and Core packages. I fear that 5 years from now Julia will have a mess of functions in the global namespace like PHP, rather than a clean standard library like Python. Is this fear misplaced?
The namespace mechanism was only added a few months ago and we're still working out some of the kinks with how it works. The plan going forward is to slice Base into an organized hierarchy but still have everything available by default without too many imports. The "using" keyword works rather similarly to the same keyword in C++ and now in Ruby 2.0 [1], and aims to give the best of both the "single huge namespace" (C, PHP, Matlab) and many small namespaces approaches (Python, Java).
Nothing more will be added to Core (though a few things might be removed), and very little more will be added to Base. Most new stuff in the future will be in separate packages and modules.
