I have seen millions of meta tags and I was curious if any of the following are important at all: abstract revisit after author I know title, description, and keywords are the most important, but I was curious if google pays any attention to these or not. Thanks for any input.
Nope.. And keywords META tag isn't used by Google either. Description META is very important in regards to SEO.
The only meta tags that are important to use are keywords (some engines still use them inspite of google. remember, google isnt the ONLY engine out there!) description and robots such as "index, follow' because it tells the bot to index and follow links on page. However, this one isnt "absolutely" necessary. Especially if you have a robots.txt file which you should. All others are waste of space.