I think both forms of language are important - spoken as well as written, it just depends what context you are using them in as well as the purpose(s) you have.
I still speech as the primary vehicle of communication- it is the form for most day-today stuff.
I think written language is more important. It is true that human use speech as "the primary vehicle of communication" (as pointed out by willbut). However, when we think of the way we learn in school, which of spoken language or written language is of more importance? Also, think about the vast cultural heritage passed down by our anchesters. When our anchesters ceased to be able to tell us their valuable experience, we are relying on their written texts. The advancement of humanity relies heavily on written language.
I'd say that day-to-day necessities rank higher, though both are important.
One has be out-spoken to lead to lead comfortable life
I think both are important but I still chose spoken language. Spoken language is like applying what you have learn, you may know how to spell or to write it well, but how you pronounce it and the intonation would make the difference. You can formulate sentences and paragraphs by writing them, you have ample time to correct or edit them. But speaking is impromptu, you have to think first before uttering a word.
written language is more important than spoken because through better writing automatically we can speak better.Besides if we are looking for jobs we must do in formal way and that is in writing formal letters which include spelling,grammar,sentence structure,punctuation and etc.Written language covered most of the skills than speaking.And through writing we know how to speak! Most people speak but worse in writing.
spoken language is better than written
In my own knowledge the written language is more valuable than the spoken language and more formal at all. Written can tell every part of the linguistic knowledge on how to use and able to apply in every part of the language and in every situation including jobs, etc and that will leads you to a linguistic competence because of your good experience and excellent in written language