Citation bookmarking

I did not know about Connotea and CiteULike -- they are great! They allow the user to capture all the citation details into their personal online social bookmarking account and share them. I quite often have new staff who do not yet use EndNote but are doing research. This would be a great way to get started and later be able to import into EndNote. CiteULike says it can do that and I'm assuming Nature's Connotea would also. CiteULike explains how to handle PubMed results when there is only one result (and apparently thus does not provide a usable URL for this system). From what I read, Connotea may import the MeSH subject headings, too.

I will want to see which one would be better to recommend.