@ivanpribec , @certik, and anyone who doubts the value of OO,
Please note there needs to be a strong cautionary tale against the cautionary tales around the problems with object-oriented programming (OOP).
As alluded to by @rwmsu , OOP must really be the last stage after considerable attention is devoted to object-oriented analysis (OOA) and object-oriented design (OOD). Often the order is reversed, particularly as someone gets enamored by OO given the influence of Java, C++, .NET, etc. and jumps head first into OOP while overlooking entirely OOA and OOD. That is a recipe for trouble.
Separately, note in the context of Fortran and similar statically typed languages, OOA and OOD can really help with packaging modular components that can also facilitate easier concurrent and parallel executions. A very simple example of this is given here.
Additionally the modular design of object components via OOA and OOD can help arrive at codes that over the longer term can be easier to maintain and extend.
Bottom-line: there are parallels with architecture with physical spaces and OO where living or working or leisure experiences and functionality and enjoyability and elegance and long-term viability and productivity are achieved by those who can bring sound analyses and innovative designs.