Yes. The theory is that through progressive enhancement we can use many new technologies at our disposal. Those who do not use the most recent browsers will not have the same experience as people who keep their browser updated, which is in fact OK. Websites do not need to look the same in every browser.

So, start using HTML5 and CSS3 now. They are a very great means to a much simpler end product. If you aren't sold on CSS3, I suggest you research some examples of people using it to essentially replace graphic design in a few cases. You can take a look at David DeSandro's resources and Nicolas Gallagher's speech bubbles. There's some great stuff to be done! And we can start doing it now.