But should unpublished authors blog or network? Sure, why not? There's no reason not to. Blogging is a fairly personal thing, even if you're talking about subjects that aren't necessarily "personal" in nature (such as this blog, which, for the most part, steers clear of my personal life and focuses, more or less, on external subjects; having a passionate interest in these subjects makes them somewhat personal). There's no reason not to blog if you want to do it. If you have something to say, say it; it shouldn't matter whether you're an unpublished author or not--if you want to do it, do it.
Social networking is somewhat of a different beast, though. While blogging can be done as an unintentional way of promoting yourself (since you can blog about taking care of hamsters and never mention your writing and still develop and audience), social networking tends to have a separate purpose. How you use social networks is a delicate process. I would argue that unpublished writers should be careful what they do with social networking; it's fairly easy to damage your reputation by being annoying with promoting your writing. Editors and publishers do notice when someone has flooded the market with amateur nonsense, and while most of them won't admit to carrying a "blacklist," they do remember names and the experiences attached to them. Unpublished writers should use social networking less as a promotional tool and more as a way to legitimately meet new people. Don't treat it as a "foot in the door" type service, because that's a surefire way of getting yourself into trouble.
The arguments against unpublished authors blogging and social networking seem to revolve around issues of time: you should be spending that time writing. While I agree, I also understand that assuming that all writers write the same--both in quality and quantity--is an unfortunately faulty way of thinking. No two writers are the same. Some writers are capable of writing for hours and hours, and others are not. For those that find themselves in a non-fiction-writing mood, or at least a non-writing mood, blogging or communicating with people online can be a welcome reprieve.
And, of course, never do something if you don't want to. If blogging or social networking isn't your thing, then don't do it. While some publishers place importance on these elements, they are far from absolutely necessary.
Now I open the discussion to all of you. Do you think unpublished writers should blog or social network? Why or why not?