I would say, that the language (under some limitations) does not matter as much, as what you do with the language. You can learn about the same about software development, algorithms, object oriented programming, computer hardware and so forth in most languages. The key is, to develop something interesting, which utilizes all of these concepts.
(migrated answer from http://cs.stackexchange.com/questions/1946/criteria-for-choosing-a-first-programming-language/https://cs.stackexchange.com/questions/1946/criteria-for-choosing-a-first-programming-language/)