From the Zotero blog:

Last Friday, Northwestern University’s Library and Academic Technologies group pitted reference managers against each other in CiteFest 2008. Students, faculty and librarians came together to run each piece of software through a battery of challenges to decide which is the quickest, most powerful, and easiest to use. We are proud to report that Zotero emerged victorious, beating out several expensive alternatives. Thanks and congratulations to Sebasian Karcher and Kathleen Murphy, who represented Zotero in the competition.

I use Zotero and it is a robust citation manager. Of course, I haven’t had to pay for (or use) the likes of EndNote or RefWorks, but if you can have it for free AND beat the competition…