Do you think shadow is important?
Our shadow insist us to walk forward....
Shadow gives more dimension and definition to your page.
shadow gives more unique dimensions and definitions to your website pages
It really depends on what you are trying to achieve in your design. There is no right or wrong here. some designs work really well with shadow. some designs don't need it at all. it's more about knowing what tools you have available as you won't use them all in every design.
Using shadows in a document can surely add dimension and depth to a page, but you definitely don't want to overdo it. Using too much shadow, or any other decoration, can turn an interesting page into a cheesy, over-cluttered page. Use sparingly. :)
Shadow events are important for design and separating art for normality!
It depends what you want
shadows can also have a beautiful effect on certain parts