You can export the contents of one blog (posts, comments, pages, sub-pages, categories) in the form of an xml file to your desktop and, then you can import the xml file into the another blog site.Your links will have to be separately exported and imported.
The instructions for wordpress.com to wordpress.com export and imports and for wordpress.com to wordpress.org export and imports are found in this post: WordPress Blog Import and Export
Instructions for xanga and movabletype bloggers are found in this post:
RSS Import Xanga and MovableType Blogs to WordPress
TT – you should also mention that there is a plugin for wordpress.org that you have to use to re-import to the new blog. That’s if you are migrating that way, which is what the export was designed for.
So, once you export from wp.com you need to download the plugin upload it to your server and activate it from your new dashboard. Then you can import your posts to wp.org.
I’ve just done it for my new blog http://www.thebritgirl.com, so I know it intimately
Hi britgirl.
I have only imported and exported between wordpress.com blogs on wordpress MU blogging plaforms and the technosailor plug-in was not required. It was easy. 
My title reflects my own limited experience: “Importing from One WordPress.com Blog to Another”.
I’m really glad you shared this. It will be useful to those moving between wordpress.com and wordpress.org blogs to know that they need to download the technosailor plugin, upload it to their server, and activate it from their new dashboard in order to import their posts. http://www.technosailor.com/wordpress-to-wordpress-import/ http://wordpress.com/forums/topic.php?id=5099&replies=9
I’ll edit the post to include this. Thanks
Yes, absolutely and thanks for adding in the detail for the plugin link. As usual I was hurrying to post… and as usual you got the links – thanks! Maybe I’ll share some of the stuff I’ve learnt to this blog too at a later date. Thanks for this forum
excellent resource. i think i’m probably the only person who would need such a thing, but you can also go from wordpress.org to wordpress.com (my post is a tad technical, as it assumes you’re already running wordpress 2.1.alpha)
great stuff! Thanks for this. Looks like we are going to be needing a lot of help!
Hi there,
I’m glad you found this to be a useful article. Soon I will have enough time to write more articles but right now I’m over-extended.
Hey,
This is the only resource I have found regarding the topic of exporting your blogroll. I need help! I have tried several variations of “http://hollandrow.tld/wp-links-opml.php” to get my OPML file in order to export it and come up with many 404 errors. Is there a step I am missing?
Again, I can’t find much information on the wordpress forums about this subject. If there is another resource to look into…
I just tried to do my own and was unsuccessful. I didn’t use the tld because that’s not in my url. I used http://myblogsname.wordpress.com/wp-limks-opml.php and as I’ve done this before without a problem I’m stumped. You will need to send in a feedback and get Mark’s help. Perhaps something changed since the new version of wordpress was done.
I apologize for not being more helpful.
Hey all – thanks for the tips. I was importing from WP MU to a WP.com (long story), and I simply added “http://YERDOMAIN/wp-links-opml.php” in Blogroll > Import Links > Specify an OPML URL … and it worked just great.
Thanks for the pointers.
Timethief’s reply: I’m glad the pointers were useful. Happy blogging
[...] Importing from One WordPress.com Blog to Another [...]
I’m hosting myself with WP 1.5, do you think I can get my site imported on a wordpress.com hosted site?
You have back dated 1.5 of version wordpresss.org software and the release of wordpress 2.2 has been slightly delayed. Given that context, I recommend that you contact staff and ask your question by emailing support (at) wordpress (dot) com.
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