This link will be active over the whole area due to the display block and the "haslayout" trip for IE6 and under. This can be done by specifying the correct dimensions or more simply by using the height:1% hack - see source code.
This block will hover in all browsers
Because an anchor is an inline element we need to use inline elements inside the anchor but we can make them look like block level elements by changing their display to block.
The drawback of using an anchor is that you can only have one link destination as you can't nest anchors.