As far as I know Yahoo is the only major search engine that still supports the META keywords tag. The question that must be asked is: how high in their algorithm to they place the META tags in comparision to words in the title, body, anchor text, etc...?
We know that the META keyword tag is still being indexed and used in Yahoo's site description. For that reason and that alone it would make sense to KEEP the field (as well as META description) if, and only if, your CMS already has it built in; and you have default keywords and descriptions so employees do not have to waste time with them.
All in all, while these META tags don't hurt, they don't particularly help either. If they are automatically entered fine. Don't remove them. I don't see a ROI should you need employees to spend any time deciding on values for either of these tags.