does keywords kept in <table summary helps>

[ststravel]

I just want to know keywords placed in the table summary will help for seo and will google will penalise for that.

[cbp]

What use are keywords there to the visitor?

If they are not any use to the visitor, then assume it could be ignored or penalized - if not now, maybe in the future.

CBP

[Kenai Alaska]

We will sometimes use the summery for it's intended purpose on pages with imbedded tables. It make it easier to work with in code view. Simular to using comments except table specific. Sometimes we use the caption for navigation tables and such but not for SEO. <caption>Navigation</caption>
I always worry about being penalized for keyword stuffing or the hated spam.
Like CBP said, "What use are keywords there to the visitor?" Include those keywords in the main text. If they are relevant to the site, this should not be a problem.
Then try to get some links with the keywords in the anchor text, it's far more important than locating them where the will not be seen.