These are the many different web design blogs that I follow. Not all of them make this list, only the ones that I think aren't trying to highlight their own work, but instead are really trying to improve the community.
Awwwards features a website every day. These websites are the cream of the crop, wonderfully styled websites. They offer reviews about the site, but I mostly use it to simply view the featured site.
Codrops explores experimental CSS techniques to create visually stunning web content. The site is minimilistic and simple to use. Ironically, it's parent website, tympanus, isn't even live.
If you really want to get into the techinical side of CSS, this is the site. The author goes into some deep waters with CSS, but some neat tricks and opportunities emerge from it.