Once you've logged into both accounts to provision Tweecious with access, it simply keeps an eye on what you've posted in Twitter and will send it over to Delicious. This also works retroactively, so you can have it slurp up all the links from your previous 1,000 tweets and send them over. For me that whole process took about 10 minutes after I had installed it and provisioned my accounts. It also adds a "Tweecious" tag to each item so you can sort which bookmarks came from Twitter.
Tweecious takes links you've included in Twitter messages and automatically saves them to Delicious--complete with tags!
(Credit: CNET Networks)
To auto-tag everything for you, Tweecious makes use of both LongURL and Zemanta. LongURL takes URLs that have been shortened by services like TinyURL or Bit.ly and expands them so they can be added and found in Delicious. It then uses Zemanta to come up with some tags, which are automatically appended to each bookmarked item. These may not always be accurate, but it's a huge time saver to have Zemanta do it for you.
It's worth a mention that this extension is still considered "experimental" by Mozilla. Shortly after installing it I noticed some slowdown when using Twitter, as well as having the post button not work for me at all. However, after it finished indexing all my previous tweets with links, everything went back to normal.
