Don't use Excerpt... At least with DotClear.
DotClear automatically generates a
meta description tag from
the blog entry, but it doesn't take the excerpt into account.
It just takes the beginning of the article content. Since the excerpt is also shown at the beginning of the article, I cannot just write 2 times the same content.
meta description is quite interesting since it is usually used
for the little snipped under a search result in usual search engines, so having
the beginning of the post in here is very nice.
This fact annihilates the good point of having excerpts.
I'm now falling back to removing progressively all the excerpts on my posts...