I write mostly C++ and Scheme and last year I wrote my first piece of code in modern Fortran (I had some experience porting/integrating old F77 libs). It's trivial to interface with C and lets you do numeric stuff immediately and without libraries using a plain syntax. Compared to C++ with template array libraries it compiles much faster and doesn't get in your way nearly as much. It has a module system... Compared to numpy/matlab/etc it takes some adjusting b/c it's still a lowish level language (errors lead to segfaults, etc.) but a lot less than going to C/C++.