Social Networking Sites for businesses - Hype? or Useful?

I think everyone at this stage knows what social networking is. But for those few that have been locked in a cupboard with a blackboard and some chalk for some 5 or so years, I'll kindly explain it to you.
Social Networking is a medium where a community of people with common interest/ideas can get together and communicate with one another over the internet.

Commonly used social networking sites would be:
Bebo (an area where you can connect with friends, put up pictures, blog, vlog. Common with teenagers, "young adults")
Facebook (similar to Bebo, but seen as an older version)
Flikr (photo-sharing network)
MySpace (same idea as Bebo or Facebook but my common with artists, particularly up and coming artists who wants to use the site as a way to get their music across to potential fans)
To be honest the list is pretty much endless. Any interest you have you will pretty much be able to find a site with like minded people.

Back to my reason for blogging.
Is this a good place for businesses to manipulate?

For advertising I think so... With the likes of bebo and even facebook where the demographic is primarily young students, then advertising your company if you are a bank or clothes shop is a very good idea.

But what I'm really talking about is companies that set up their own page in these social networking sites.

If you look at MySpace... this is a great place for new artists to get their music across. Lily Allen became well known because of her MySpace. She couldn't get a record deal and therefore starting putting up vlogs of her singing songs and got the biggest response in MySpace history. And the rest as they say is history. This was a great business idea for Lily and is the primary reason for she is today.
Definitely not hype.

In the area of pubs and clubs. I myself have both a bebo and facebook account (though if I'm honest the bebo account is pretty redundant these days). But with facebook loads of pubs and clubs back home have their own facebook page. I personally think this is a great idea because with Facebook if you're friends with these pubs and clubs you automatically get details of whatever they're talking about.
EG http://www.facebook.com/profile.php?id=100000071358759&ref=ts
The link shown above is for Patricks Bar, a new bar opening in Ennis, it used to be called Moscos. Anyway they're opening their doors this coming friday 09/10. Considering they are a new pub with a brand new name, so not that well known, most of their future customers will be students or people who're working outside the town and therefore will not hear the news of the bar opening. So what do they do? They go onto the pages of other bars in the town find their friends, and ask them to be their friends. Which happened to me. I got a request from Patricks Bar to be my friend. So whenever Patricks Bar makes a new post about when they're opening or new promotions, when I log onto my page I will see their news. Therefore I will know Patricks Bar is opening on Friday. Free publicity. What's so wrong with that?
In that case, its definitely not hype.

I think for businesses to get ahead they have accept that this is the way of the future and therefore have to get on board. Social networking sites aren't just fun childlike sites like bebo and facebook. There are social networking sites available for business minds
EG http://www.sitepoint.com/blogs/2009/07/28/social-networking-sites-for-business/
This link shows a list of social networking sites focused on business users and meeting their needs. Showing there is a place for everyone.

Therefore social networking for businesses is definitely not hype. You just have to know how to work it to your advantage is all.