This is all a bit experimental, but I’ve just asked Elgg to post any new items from my del.icio.us feed with the keyword “linklog” to my main blog. When the RSS gets grabbed later on tonight, you should see a link to Wired News.
This functionality, although we’re watching it closely and it’s nowhere near finalised, means you can (for example) maintain your blog on WordPress but have the content also posted within Elgg. Right now you can select the tags new posts from each feed will have; later on you’ll also be able to set a default access level.
To make this work, just go to your resource tab and check the box next to the name of any feed you want to import. Imports don’t happen instantly, but the next time that RSS feed is grabbed, any new content will be posted to your blog.