I might have been unclear what I meant. I believe that the description is used. But only to show as a result. Not to index.
From that page:
[edit] The keywords attribute
The keywords attribute was popularized by search engines such as Infoseek and AltaVista in 1995, and its popularity quickly grew until it became one of the most commonly used meta elements[1]. By late 1997, however, search engine providers realized that information stored in meta elements, especially the keyword attribute, was often unreliable and misleading, and at worst, used to draw users into spam sites. (Unscrupulous webmasters could easily place false keywords into their meta elements in order to draw people to their site.)
Search engines began dropping support for metadata provided by the meta element in 1998, and by the early 2000s, most search engines had veered completely away from reliance on meta elements, and in July 2002 AltaVista, one of the last major search engines to still offer support, finally stopped considering them[2]. The Director of Research at Google, Monika Henziger, was quoted (in 2002) as saying, “Currently we don’t trust metadata”[3].
No consensus exist whether or not the keywords attribute has any impact on ranking at any of the major search engine today. It is being speculated that they do, if the keywords used in the meta can be found in the page copy itself. 37 leaders in search engine optimization concluded in April 2007 that the relevance of having your keywords in the meta attribute keywords is little to none[4].
Anyway, I agree that it’s a bad idea to ignore them altogether. Which is why I originally got the tags module. I also agree that nobody knows how google actually does manage ranking. Course I guess the reality is, if they made it public the first thing that would happen is people would abuse it!
you can, as mentioned, also put the summary only in your meta ‘description’ or ‘keywords’. that’s one thing that’s really gret about EE. you can put things anywhere with very little effort.
here’s how I added my keywords using the tags into meta keywords:
{exp:weblog:entries weblog="{master_weblog_name}"}
<meta name="keywords" content=" {exp:tag:tags entry_id="{entry_id}"}{tag},{/exp:tag:tags} "/>
<meta name="Description" content="{title}"/>
{/exp:weblog:entries}
If you wanted to use just the summary of your article to add to the description you can do that like this (which of course doesn’t require doing any add-ons):
{exp:weblog:entries weblog="{master_weblog_name}"}
<meta name="description" content="{summary}"/>
{/exp:weblog:entries}
FYI obviously I don’t work for EE, so they could easily have better responses for you