WordPress.com have announced portfolios designed to provide photographers, videographers, illustrators, painters, designers and others who want to showcase their creations on WordPress.com
There are over 30 portfolio themes to choose from and themes let you set a custom header image and a custom background image or color.
Custom Design upgrades enable you to make your blog look and feel exactly the way you want.
More info: http://en.blog.wordpress.com/2013/01/16/showcase-your-creativity-with-a-portfolio-site/