There are Numbers of Myth going on SEO, like use of META tags, Google Page Rank, Keyword Density, etc....... Every one have it's different views about the above mentioned topics and many more like those. So why don't you reply and put your point up here so the points can be cleared !
I personally use meta tags, i cant see why not to, it adds to relevancy when used correctly. I dont think of keyword density, i just write, if your thinking of keyword density then your not writing naturally. PR does matter, otherwise it wouldn't exist, just dont chase it, it will come if a site deserves it, just remember it can easily be stripped away, oh and dont sell it.
Good point theres too much behind the scenes stuff for us to keep up, and google want to keep it like that i guess.
Meta tags were being spammed and hence search engines have reduced their value (and justly so). But they are not useless, I still use unique meta tags for my sites if it's possible. (You won't get a duplicate meta description error in webmaster tools if they didn't give any weight to meta tags). About PR, it's an integral part of google's ranking algorithm and is not totally useless. Apparently, two of your mythbusters did not work on me
Pr is considered in the ranking algorithm but its a factor just like any other. not a very important one (personal experience).
Meta is HUGELY important. I can get a site to rank for any keyword (one that are not too competitive) just through meta and onpage optimization!
Check out this post (I still can't add links to dp so just delete the white spaces) www. seosapien . com/blog/2008/12/seo-myths-and-facts.html
Nobody knows for sure what actually gets top rankings. Its all based on personal experiences shared on with other SEO experts. These are theories, not myths! They are tested until proven to be correct.
Ah.. My experience has been quite opposite. Except for meta description(which works as the text displayed on SERPS page), none of the other meta tag makes any difference in SEO.