Serious questions about tags and categories (WORDPRESS BLOG) Need Expert Advice

I would recommend adding the meta noindex to your tag pages to avoid problems with duplicate content, which is one of the biggest SEO issues with wordpress sites. The YOAST SEO plugin will take care of this for you.

Notwithstanding the above, you should always write a unique meta description where possible as this is your pages advert in the SERPS and while not directly affecting rankings, will affect click throughs.

Tags have very little impact on SEO rankings. The only real benefit of them is that they inform Google that a page has relevance for the keywords you tag. But if you create your content with a focus on those keywords, then chances are Google already understands the relevancy of your page.

Tags are really just a mini helper to search engines. I don't even waste my time on them because pages should demonstrate keyword relevancy to the point where no tags are necessary.

P.S. If you want to test it out, try creating similar pages on keywords with and without tags. The SEO difference between the pages will be negligible.

Setting tags (or categories or whatever archive pages to NOINDEX) makes only sense if your archive pages would show FULL content.

They should always only show excerpts - and not duplicate your full posts on the categories or tags archive pages. Then it's *relatively* irrelevant whether to no-index them..but that being said, it depends on your site and whether on your site tags OR categories make more sense whether even to use categories/tags. (Some sites just won't make for a whole bunch of categories)

---> I had VERY good ranking success adding tags to posts.

Why?

It allows a certain freedom to add keywords to a post which otherwise are not in the content and I had sites seeing ranking for their TAG keywords alone in Google! On the other hand, you should not over-do it with tags because tags can be tempting to stuff all sorts of keywords to content. (for a product review, say product name, brand, review, reviews, xyz review, clickbank, etc..etc..)....so don't do any short, thin content and then add 20 or so redundant tags because it will (likely) be seen like keyword stuffing. That being said, to answer your question, I would say tags are better.

davidmcsweeney covered it perfectly. I agree with him 100%.