Hello,
I have a question. On my index.html I have the meta tag <META NAME="revisit-after" CONTENT="7 days"><META NAME="robots" CONTENT="FOLLOW,INDEX"> , but I do not think google is re-indexing my site. Do I need to keep relisting my site, or will I get blacklisted with Google? I need Google to keep indexing my site, as my keywords can change. Thanks for your help in advance.

In general Google will only index sites once every month, in the run up to the 'Google Dance' (around the end of the month). If your pagerank is above 5 or 6, you may get visited by Freshbot, which goes to more popular sites and updates listings every day or week.

I don't think Google pays much attention to revisit-after, in respect to visiting more frequently, its open to abuse, but it may work if you set it higher than 1 month (e.g 45 days).

It's very difficult to predict anything with Google at the moment, though, as it seems to be undergoing fundemental changes which could chagne the way the whole system works.