>This is a little awkward to explain in English, but I want it to reach a larger audience.
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>When the author addresse the reader, in English he will write "you" (e.g., "now you can..." or "do this and that...", with the "you" implicit).
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>In Spanish, there are four forms of "you"; apart from singular and plural, there is also the distinction between a more formal manner ("usted", in the singular), and the more familiar one ("tú" in most regions).
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>There is a similar difference in most other languages.
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>Now, I was wondering which of the two forms is considered more appropriate to address the reader, either if someone writes an article in Spanish or Portuguese, or when translating into one of these languages.
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>I guess both are acceptable, but anyone want to give his opinion anyway, about his preference in this regard?


I would go with usted. If my shaky memory of high school Spanish is correct, tu is appropriate with friends and others one knows well enough to speak with in a familiar way. That would not seem to describe a reading audience, especially if the material is non-fiction (such as a technical article). In fact I wonder whether the reader needs to be addressed directly at all in that type of writing, either formally or familiarly. Shouldn't it just describe the subject material?