Output of BibTeX now includes tags in a field called "keywords", which is more common than "tags". When importing BibTeX, both fields are merged.
If you post a single BibTeX snippet, which you already have, you can see the duplicate on the edit bibtex page. Furthermore the postBookmark button has been updated: selected text from the page is now automatically included in the description/comment field. On the settings page you can now update your email address, as well as your homepage and real name.