The good I see is that the markup is absolutely minimal, although I'm disappointed that the developer didn't give a unique name to the css in the examples. I see so many developers complain about CSS but time and time again, I see that the problem isn't that CSS is some terrible archaic language, it's that developers create messy markup that forces CSS hacks to correct them. Nevertheless, this website does a great job in not exactly showing the 'What' but the 'How' which leads to my next point.
The bad I see is that unless these effects are edited to match a more complete brand style guide, they just look like gimmicks and will do little to 'delight' any user.