1. Yes, although initially a lot of them will be displayed in the serps but overtime the search engines should work out that you are the originator of the content and the other websites will be weeded out of the search results. To test this run a search for the title of one of the latest seomoz blog items then run a search for a very old seomoz blog item. The recent one will have loads of duplicate results but the old one will most likely just have the original seomoz blog.
2. Article directories were penalised in the panda update and have had their ability to rank and pass link juice reduced. Don't expect to get too much value from them, you should get value from any other sites picking up the article though.
As an alternative to article syndication is may be worth considering doing some guest blogging?