There is also another advantage to Less/SCSS, which is that existing CSS files are already compatible, so you can start a gradual migration without effort.
This means for instance that an outside designer, that does not know Sass, can come in and contribute directly to the codebase without his workflow being disrupted and without me having to tutor him in Sass. This is how design works anyway - you start with a bunch of PSDs that get accepted, you transform that into static HTML and CSS (that have to be emailed around and approved), then you start adding dynamic features, you then go back to the designer to fix the design in case the dynamic content doesn't blend well, then you start refactoring the HTML/CSS to be clean and easy to maintain ... but this is only the last step, because the other steps, like getting the design right, are more important.
When you say that Sass should be the true successor to CSS, you're thinking like a programmer. I also wish that Gimp would be the true successor to Photoshop, but that won't happen.
> There is also another advantage to Less/SCSS, which is that existing CSS files are already compatible
Not sure about SCSS, but in my case Less choked on some complex hacks like IE filters. Not arguing about their evilness, but the fact remains—not always you can simply rename .css to .less and gradually start using new features. (In the end I kept CSS as is, with a separate Stylus file with overrides and new styles. SCSS wasn't an option, and I have a feeling it also suffers from these issues.)
There is also another advantage to Less/SCSS, which is that existing CSS files are already compatible, so you can start a gradual migration without effort.
This means for instance that an outside designer, that does not know Sass, can come in and contribute directly to the codebase without his workflow being disrupted and without me having to tutor him in Sass. This is how design works anyway - you start with a bunch of PSDs that get accepted, you transform that into static HTML and CSS (that have to be emailed around and approved), then you start adding dynamic features, you then go back to the designer to fix the design in case the dynamic content doesn't blend well, then you start refactoring the HTML/CSS to be clean and easy to maintain ... but this is only the last step, because the other steps, like getting the design right, are more important.
When you say that Sass should be the true successor to CSS, you're thinking like a programmer. I also wish that Gimp would be the true successor to Photoshop, but that won't happen.