Not a Pretty Picture for Avon, Stock Down  NEW YORK (Reuters) - Avon Products Inc. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=AVP.N target=/stocks/quickinfo/fullquote"&gt;AVP.N&lt;/A&gt;, the  world's largest direct seller of cosmetics, on Wednesday  forecast a slide of as much as 10 percent in U.S. operating  profit as it grapples with weaker sales of key beauty items.