Don't worry about the keyword meta tag on your website. Google
ignores it (and has
65% of the global search market: it's nearest rival has 8.2%). At Bing, using the keywords meta tag
might actually harm your ranking.
My own advice would be this: write good content, don't try and optimise for search engines. Search engines are a constantly-moving target, since they're constantly tweaking and adjusting their algorithms. Those tweaks are always designed to do one of two things: (1) make them better at finding good content or (2) make them better at ignoring sites that use SEO instead of writing good content. In other words, if you write good content, the search engine's programmers will be doing SEO for you
