What is the effect of web 20 submission in SEO?

What is the effect of web 20 submission in SEO?

What is the effect of web 20 submission in SEO? there are some web 20 site list

PR8

tripod.com
tumblr.com
typepad.com
weebly.com
blogger.com


PR7
jimdo.com
posterous.com
yola.com
squidoo.com
multiply.com
angelfire.com
officelive.com
rediff.com
wikidot.com
webs.com
salon.com
webnode.com


PR6
moonfruit.com
edublogs.org
soup.io
ucoz.com
webspawner.com
travelblog.org
gather.com
springnote.com
freeblog.hu
blog.com
webstarts.com
journalspace.com
blog.de
onsugar.com
quizilla.teennick.com
areavoices.com


PR5
freeflux.net
freehostia.com
zoomshare.com
blogdrive.com
blogtext.org
flixya.com
webgarden.com
ohlog.com
livelogcity.com
snappages.com
sosblogs.com
visualsociety.com
insanejournal.com
blog.hr
blinkweb.com
ewebsite.com
alivenotdead.com
hazblog.com
hpage.com
blog.com.es
350.com
beep.com
devhub.com


PR4
inube.com
iseekblog.com
flukiest.com
bloggum.com
hipero.com
blurty.com
bloghi.com
wallinside.com
getjealous.com
fotopages.com
wikipages.com
freeblogspot.org
mywapblog.com
yousaytoo.com
myblogsite.com
spi-blog.com
2itb.com
mytripjournal.com
blogreaction.com
doomby.com
blogge.rs


PR3
weblogplaza.com
spyuser.com
publr.com
blogster.com
bcz.com
iblog.at
honmag.com


PR2
blogpico.com
uwcblog.com
evood.com
please give me best answer thanks