A couple of nights ago, while out with other DjangoCon attendees I exclaimed, "What am I really into right now? I'm totally into CSS." They looked at me as if I had said that I loved the audio quality of cassette tapes.
Yeah, I'm kind of into CSS and it's limited functionality.
I think a common mistake that we programmers make is that we assume that more functionality is always better. Kind of like, "What if someone wants to do x? Then we better provide the ability to do so!" While in reality, nobody is currently doing x and adding x creates an unnecessary rule that will need to be maintained.
The beauty of CSS is that it's so simple and has so few rules. In fact, I don't know how they managed to keep programmers from messing it up for so long.
My pal Jon Rohan passed along this great article about generally discussed features for new versions of CSS. Some of them I could see being very useful (variables, basic math), while others I find a bit too much like that aforementioned x.
Right now I've been finding lots of tools to help with my exploration of web design and CSS. The most useful tool is definitely the "meyerweb reset" stylesheet followed closely by the Firebug Firefox extension and ReCSS bookmarklet.