I have another blog that also run on WordPress which I had been adding tags and I never really understand the idea of tagging. I had been inserting 20 or more tags in each post. Then I did some research and found out about web sites can be label as spammers because of too many tags on each post.
It is called tag spamming check out this WordPress forum.
I never heard of the term tag spamming before and it only happen if you have more than 10 tags in a single post. Also, since search engines doesn’t care or cannot tell from category and tags. Which mean you will have to count the total number of tags plus your category and make sure both do not exceed 10.
Make sense to me, but now I have to go back to my other blog and start removing the extra tags.
If you are lazy like me and doesn’t want to do any extra work when it comes to tagging your posts. Check out this WordPress Auto tagging plugin, it automatically displays all the related tags in your post and you have the option to select each tags you want to be inserted.