I look at it like this...
Myspace.com is for kids, I log into it maybe once or twice every few months just to keep my page active and see if anyone interesting wants to add me!
Facebook.com is for adults, it's simple, no bling bling HTML around or 100's of little animated starry gifs bogging down powerful computers...
Affluence.org is for wealthy folks, to sit and talk about how to make more damn money... it's nuts... but a great learning tool.
I use all 3 (only got onto Affluence thanks to the boss man, you can get "Invited" to join by verified rich assholes, of which I am not... maybe an asshole, just not rich
)
But, all in all... Facebook is the most simple way to keep in contact with the many friends I've met from all over the world, and you can keep in touch on an everyday basis which is great, no more international call charges!