I saw a number of sites eg., GigaOm hosted images using Wordpress.com for example this image from this post: http://gigaom.com/2009/11/13/dell-wisely-chooses-emerging-markets-for-smartphone-play/ pointed here: http://gigaom.files.wordpress.com/2009/11/viewmedia.jpg?w=108&h=144 How did they do that?
Yes have to signup for wordpress.com and then , select "add new" post and then in the adding contents box, click upload image and select the image from where you have to upload then click upload, you can two options browser upload or flash uploader depending on your net speed and content. then select "insert into post" if you need a back up of image in your wordpress server select "save " then you can find your image posted in your site.