Best rticle submitting sites, publishing, submitting/distribution, vBulletin

Can someone suggest the best article submission sites?

These sites also offer publisher accounts. Is publishing any better than submitting articles for distribution? How does that affect PR and backlinks? Which one would you recommend?

If I go for publishing and later decide to distribute, will all previously published articles from the same source get re-distributed as duplicate content?

For vBulletin CMS, what is the best way to place article publishing on auto-pilot (POST method)? Is it possible to post articles automatically or are there any plugins for vB? How/where do sites such as Yahoo get their content from?

TIA

 

for yahoo, they do lots of effort to get contents.
and "Triond" is best site for Article publishing i ever see

 

Please edit the title of the thread. It should be Article not rticle.

 

I tried to edit the typo in the title while it allowed me but it only updated the post title and not the thread title. Thanks

 

ezinearticles i think