You answered your own question.

The meta-keyword tag has been dead for a few years.

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Yahoo and Bing still using these keywords

Thanks for the answers.

Meta keywords or description have no important in eyes of Google at least, nor these affect on any SERP improvements. If you like you can add catchy and relevant description to attract the visitors from search results.

I have seen a Matt cuts video where the told that Google Didn't give important to meta-keywords. so, i think Yahoo and Bing still give importance to this.

no but i still use them as a guide for myself reminding me (and my content writers) what keywords I am targeting for those pages.

Meta tags have little to no significance when it comes to SEO. Linkbuilding is key for SEO for now.

Meta tags have no importance in the spider of Google.therefore it is an important in yahoo and bing.

I also had seen a video in which Matt cuts said that Google don't give importance to meta keywords. But i personally observe that Yahoo and Bing is still loving it. Google Prefer Title.

Thanks

Like everyone's been saying, Google doesn't care but Yahoo and Bing do too...In addition to this though almost all 3rd Tier Search Engines use them as well. My opinion on the matter is "Who Cares?" They're quick and easy to implement and what's the harm in throwing them in there anyways.

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