Your ultimate frontend email validation
Leverage native APIs, otherwise check only for @ and go grab another beer.
Thoughts on the status of web development
It is nice to have free powerful stuff, but let's not forget about the standards.
Microdata for Rich Snippets
Wrap semantic blocks, use HTML classes for styling and read the manual.
CSS limitations on IE
IE 9 has a hard limit of 4095 selectors per stylesheet. Size does not matter here.