Twitter - http://www.twitter.com/
*Listorious - http://listorious.com/ - Twitter Lists & Listorious Review
*Twibes - http://twibes.com/ - Twibes Review Haptree
MySpace - http://www.myspace.com/etsy
Facebook - http://www.facebook.com/
Stumble Upon - http://www.stumbleupon.com/
Craft Focussed Social Media
By Hand - http://www.byhand.me/ - ByHand Review
CraftStylish - http://craftstylish.com/
Mixxmade - http://www.mixxmade.com/
Blue Canvas - http://www.bluecanvas.com/ - Artists
Get Crafty - http://www.getcrafty.com/
Page Flakes - http://www.pageflakes.com/
You Craft - http://youcraft.org/
ArtsCollab - http://artscollab.com/
Online Handmade Market Places
Folksy - http://www.folksy.com/
Misi - http://www.misi.com/
Etsy - http://www.etsy.com/
* CraftCult - Heartomatic - http://www.craftcult.com/heartomatic.php
* Craftopolis - Treasury Clock - http://www.craftopolis.com/index.php?com=tc
* Cr8tivity - http://cr8tivity.com/
Artfire - http://www.artfire.com/
1000 Markets - http://www.1000markets.com/
Online Marketplaces- Sell Anything
http://www.craftjuice.com/ - Craft Juice review (Swirly Arts)
Directory Submissions and Pinging
http://www.postaroo.com/ - invite only?
http://card.ly/ - Profile Hub
Still to be categorised - this is a work in progress!
If you would like to join in and write your own review of one of these links or another site you've found that should be on this list, then please email me and I will use your review to create a post. It doesn't need to be an essay, just a few pointers and I will of course include an image or two of your work and a link to your shop within the post by way of thanks!
Don't forget you can add a comment with a link to your own site if it's helpful to crafters/bloggers here and it may get reviewed!