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Forum Moderators: mademetop
Stuffing HTML Comments and this summary tag that you refer to with keywords and keyword phrases is real amateur stuff from my perspective. There is no need to pollute your <html> real estate with these non-indexed tags. They serve no purpose and they add to the overall page weight.
Now, there may be instances where certain metadata is used by the education industry or by a corporate intranet search. Sometimes you will see metadata that is specific to these types of scenarios. For the most part, from an SEO/SEM point of view, you'll use the...
META Description Tag
META Keywords Tag
In that order. Any other metadata you have in addition to that is most likely author info or possibly a PICS rating or some other obscure piece of metadata.
Anytime you find your self cutting and pasting exact blocks of indexible content, think to yourself is this correct? There is no need to have a keywords tag and then an abstract tag with the exact same string of keywords. In fact, many abstract tags that I see being utilized are improperly formatted and leave a bad impression on those of us who know better! ;)