CSS web galleries are a really useful and important resource for graphic and web designers. They can be great for getting new ideas and inspiration for graphics, web designs, layouts, logos, and basically all things design.
They are also another way to improve search engine optimization and page ranking, by having several incoming links to your site from other notable websites. This is obviously very important for when people search for a keyword, the most relevant results that are returned are partly based on the PageRank of certain page. So the more links to your site from sites that aren’t considered spam, the better off you are all around.
However, I did not make this list for people interested in submitting their site to CSS Galleries, at least not entirely, because there are a very large number of these types of sites, and manually submitting yours to some or all them would take time, and you might want to consider your options here first before doing so. Outlaw Design Blog gives some insight to alternate ways to for getting your site listed on CSS Galeries