I don't give a shit about any of those sites,but then I'm not a producer or promoter. So I'd only be there for the social aspects.

To be honest,I've been a little supprised over some of the people I've seen on myspace.(I've looked,but like you say,it takes feckin ages for a page to load) There're loads of well known techno producers on there. Don't do it man,keep some credibility!! It's just a big f*ck off advertising/data collection scam anyway :)