They become a problem when you have them but don’t use them correctly and your site has 10,000 + dynamically created pages like mine. I had meta tags and good ones. The problem, they were all the same for all the pages. The title and content were different, not the meta tags though. What did I find? That no matter how unique the title or content was if the meta data was a match to previously listed page, then all new pages would show as sup. results, which sucks. So now I make sure to at least include what is different in the title in the keyword and desc. meta tag. Good pages will not list because this stupid little fact. It may be better just to use no meta at all in my case. You can see an example of this now by doing site:http://www.freepokerleague.com on google, you will notice only two links listed when I have over a thousand indexed, they all had exact matching meta tags. I fixed this so this example may not last long. I have no other known bans or filters so this was my conclusion to why I haven’t listed well with all the other pages in my site.