Wall St Set to Dip, Bank Results Dominate  LONDON (Reuters) - U.S. shares were seen opening a touch  weaker on Wednesday as markets mull the Federal Reserve's  cautious assessment of the economy and await third-quarter  results Morgan Stanley &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=MWD.N target=/stocks/quickinfo/fullquote"&gt;MWD.N&lt;/A&gt; and Bear Stearns &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=BSC.N target=/stocks/quickinfo/fullquote"&gt;BSC.N&lt;/A&gt;.