Well, some people are always looking for the latest and greatest. If you don't have "new" items then how does the customer know they are not buying last years model, or an obsolete product? Or worse, how do they know the web site is still active? In other words, "new" is good!
"New"can be overused, like putting it in bestsellers for instance. How can it be a "bestseller" if it is a recent addition? Does that mean your other products don't sell, just the "new" ones? :P It is a double-edged sword.
Customers want to see "change" when they revisit a web site, and "new" equals change. So does "sale", but if either are overused they become pretty much meaningless. I have seen several retail stores that advertise "going out of business" sales for months on end. There was even one that did so for years. When they actually did go out of business recently, no one seemed to pay attention to yet another "going out of business" sale.
