You are incorrect. It does plenty and it's read by most spiders, it's a dumbed down page-centric version of a robots.txt. It may not do much for you and your sites, but it's a valid <meta>.
It may be a valid Meta but it does nothing to encourage indexing with any of the major search engines. More mistakes can be made with it possibly doing damage to your site.
yfs1 is correct -- you re wrong, da22in. That instruction, "index, follow", simply says "index this page and follow links to other pages". That's what all spiders do by default. Therefore it is a waste of space. If you do NOT want the default, then it becomes useful (although it may trigger suspicion): "noindex, follow" = don't index this page but follow the links out "index, nofollow" = index this page but don't follow the links out "noindex, nofollow" = don't index this page and don't follow any links on this page
I have found lucrative results by also including a meta rating from ICRA and then entering a review in Alexa stating that the site is kid friendly. <META HTTP-EQUIV="pics-label" CONTENT='(pics-1.1 "http://www.icra.org/ratingsv02.html" l gen true for "http://www.yoursite.com" r (nz 1 vz 1 lz 1 oz 1 cz 1))'>
That's really not going to do a lot for SEO -- it may help to the extent that your page will display for someone using an adult filter of some sort but the page has to be found for that to matter -- Alexa isn't going to help a whole bunch in SE ranking.