“Meta tags are a great way for webmasters to provide search engines with information about their sites”

https://support.google.com/webmasters/bin/answer.py?hl=en&answer=79812

It is the most rehashed, repeated and abused topic in the business. Meta Tags are useful, OK? Matt says so (Matt Cutts is the voice at Google concerning best practices for building and maintaining websites – webmastering).

Now lets move on and talk about this like professionals, and not like tabloid reporters. Meta Tags are one of many ways to communicate with search engines. As I write, its becoming very clear that Schema Tags are the new black replacing Meta Tags in terms of ROI on your optimization efforts. That means those websites that use Schema Tags sooner, will benefit in search results. Spending time massaging your existing Meta Tags will have a lower ROI than implementing Schema Tags.

Scheme Tags are not the only “other” tags. Geo Tags and Alt Tags are all excellent opportunities for SEO (search engine optimization). Why? Because so few websites use them at all. And if they are used, they are often poorly implemented. Even many contemporary web platforms do not implement these tags by default – yet.

Why they will get you ahead in search

These tags specify what the data on a page is about in a standard format (generally agreed upon), therefore its easier for the search engine to determine what the webpage is about rather than spend precious computing cycles reading all the text on a page, computing keyword density, and sort out potentially deceptive keyword-stuffed content. Why would a search engine NOT read and use these tags? And what search engine (that cares about its SERP accuracy and compute cycles) would not give some incentive to the webmaster community to implement said tags?

In general, those voices that disregard implementing or utilizing these SEO opportunities are either disingenuous or lazy.