Back when Myspace was the hottest thing out for artists, some artists were forwarding their official domain name to their Myspace site. Now I am starting to see artists forward their domain to Facebook. Those are both terrible ideas.
Your official website should be your hub of information to feed Myspace, Facebook and Twitter.
The reason I think, forwarding your domain to Myspace is terrible, is because you are branding Myspace more than your own brand. Myspace is making money off your own site every time a user goes there. Wouldn't it be wise to run advertisement on your own site and collect that income? You should be your own entity. Myspace collects all your data from their page, you don't….same goes with Facebook.
Do I think it's a good idea to have a Facebook page? Absolutely! Facebook has grown to over 400+ million users, making it the biggest social networking site on the internet. Think of all the fans you can capture with sharing information about your upcoming tour or album on Facebook! Facebook has a huge potential for every artist, public figure or celebrity to share content.
When you are tweeting out links, you shouldn't be tweeting out external links to everywhere, you should be tweeting users to your official website. That way you are building your fan base bigger and bigger. I think a lot of people are forgetting about "archives." For example, say you posted a link on Facebook or Twitter about your tour and it was to another site. Eventually as tweets and Facebook status updates increase, that link you posted gets pushed down the timeline making it impossible for someone to find. However, if that link you posted was on your own website, users could visit your site and use search.
Your hub should look something like this: