First conclusions

Grid systems enable fast conversion from drawn designs to actual html. The price is hard-coded layouts (table-based design with a different syntax). The counter argument is that no one ever changes the layout without changing the markup, anyway.

Of the bunch, YAML and YUI are a bit more flexible, enabling some kind of source order independence and some kind of switching layouts by only switching the css.

Community wise, YUI is the biggest, but the CSS is just a part of the whole YUI. And YUI Grids 3 is not there yet. Next are Bluetrip and YAML (bigger in German than in English) and 960.gs

License wise, they are all GPL/MIT, except for YAML, which uses a CC-A 2.0) licence, and does not seem to follow Creative Commons recommendations NOT to use CC licences for software.

You still have to know css. You still have to work on the styling, once the layout is done (with the help of reset, typography and base css files). None provide variables, code reuse. (see lesscss to get an idea of what I mean.)

There is a debate about thou shalt not edit these files vs use generic files, but customize them. Each side has its argument: maintenance and standard vs size and (slightly) speed improvement.

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