- Patch from Matt:

"The noise words description says that whitespace and line breaks will be
  stripped out, but the code never does any trimming.  This simple patch strips
  the whitespace from the noise words.  This probably takes care of bug #2804."

modules/search.module

@@ -270,7 +270,7 @@ function update_index($search_array) {
       // Remove "noisewords"
       $noise = explode(",", variable_get("noisewords", ""));
       foreach ($noise as $word) {
-        $wordlist = preg_replace("' $word '", " ", $wordlist);
+        $wordlist = str_replace(trim($word), " ", $wordlist);
       }
 
       // Remove whitespace

modules/search/search.module

@@ -270,7 +270,7 @@ function update_index($search_array) {
       // Remove "noisewords"
       $noise = explode(",", variable_get("noisewords", ""));
       foreach ($noise as $word) {
-        $wordlist = preg_replace("' $word '", " ", $wordlist);
+        $wordlist = str_replace(trim($word), " ", $wordlist);
       }
 
       // Remove whitespace