Is it considered duplication if I transport the URL to ezinearticle.com and other article sites.

You cannot post the same article on different sites, not only will it be flagged as duplicate content but it would also rank low in search engines.

You can write a completely different articles promoting the one you wrote on Hubpages and link to it aswell. You will rank higher if you get traffic to your hub from ezinearticles.com or any other similar site. Just try not to over do it, they might think your'e a spammer.