Social networking and all that

Good evening...
I have looked at each of the examples of social networking in action and I can see that these institutions are using MySpace etc to great effect. Their sites are eye-catching, informative and provide lots of opportunities for members to interact with the site which is so much the expectation of contemporary culture, or at least youth culture.
I was particularly interested with the local Government Communities of Practice example which is much 'bigger' than libraries but could offer great potential for enhancing the social fabric. The East Renfrewshire Council example was also interesting because it was simpler and therefore more accessible to me than some of the others, impressive though they are. I could see something like it as being only just out of reach of this library.
It could be just that I have been toiling over this course for five hours today but the different applications - blogs, wikis, social networks - are starting to merge together in my mind. They all seem to involve networking in the sense of sharing ideas and inviting interaction and where does one out-perform another? I guess these social networking sites have the advantage of already having a high profile in the cyber-world - even I have heard of MySpace and FaceBook although I had never visited them before today. And the sample sites are so comprehensive with pictures, blogs, videos and podcasts, posts, links that perhaps they incorporate individual elements that we have previously looked at like wikis and blogs and videos - encompass the lot.
For libraries who have staff with the expertise and time to maintain sites like these, a page in MySpace would be great for client marketing and interaction. For one of the earlier applications - I forget which - I thought no-one would be likely to find the library's entry, but that wouldn't be such an issue on MySpace. For networking at the professional level I think you would use a wiki or a more closed environment like that.
But the course asked about possibilities for my library using social networking and they don't look good. Apart from the veracity of that user name, I can't imagine myself ever having time to manage such a site, bearing in mind that a poorly maintained and presented site is as much a 'put-off' as a well-constructed, attractive and informative site is a 'come-on'. I note that the NewsGrist article suggested that at least for that institution the maintenance of a presence in MySpace was effective in increasing interest, usage and interaction and that managing time is based on balancing competing priorities and not always doing the existing tasks because they have always been there. A modest blog might be a better spec than the current printed Newsletter. But the latter takes about five hours once every six weeks - an effective MySpace page would take a lot more than that!!