For the first time in ages, I saw today a job announcement in Armenia with indicated salary information. (well, there may be others too, but it’s something very rare) I always wondered why people would not indicate this one of the most crucial factors in deciding which job to take in their announcements and leave it to speculations, as something 'unspoken', 'guessed'... Is this some kind of false morality thing ("we do not care about money, we care about job"). Or perhaps it's US influence too: it is very common in US to withheld salary info from the announcements.
Only in rare cases when salary is negotiable and pretty high it may be OK to put some sort of vague indications of it. Otherwise, I think it should be a norm. For example, in the UK and Europe salary information is normally an important part of any job ads.