After migrating blogspot blog to Wordpress, do we need to delete the blogspot blog to avoid duplicate content?
Eventually, yes. However, you may want to leave the old one up for a while and have the last story on it point to the new one. Once most of your normal reader base have noticed the change, then you can delete the old one if you're worried about duplicate content.
I don't think you even need to do that if the Blogger site was on your own domain (same as the WP site). I made a switch, and took my Blogger site down within a few days.
So you mean if i move from xxx.blogspot.com to xxx.com i should delete the blogspot so that my xxx.com site powered by wordpress won't get penalized?
Not sure which of us you are referring to, but I meant... If your Blogger blog was using xxx.com, rather than xxx.blogspot.com, then you can pull it down. And if you own the domain xxx.com, I expect there are a few people here who'd like to make a deal with you!
no, u are getting it wrong. Lets say my blog is abc.blogspot.com, after 1 year i have decided to move all the post in abc.blogspot.com to www.abc.com, so now both abc.blogspot.com and www.abc.com have the same posts. So the question is should i delete abc.blogspot.com so that it won't cause any trouble to www.abc.com as duplicate content.
I've left old content up after migrating to a new system. No duplicate content penalty. I don't think there is one for only a couple of sites being the same. The old pages continued to get profitable hits for a year or so. Richard
Check out these links: http://codex.wordpress.org/Importing_from_other_blogging_software http://www.quickonlinetips.com/archives/2006/03/import-blogger-posts-comments-to-wordpress/