It must be Zotero week. Today the CompuMunkey blog reports that you can now import EndNote styles into Zotero! I gave it a brief test and all seems to work as intended, though as I posted yesterday I'm now using the beta of Zotero 1.5 for its new sync feature, so I'm not sure if this works under version 1.0.6.
This has been one of the few points that Zotero has had to concede to EndNote -- Zotero ships with a handful of styles, and EndNote ships with, what, 2500? Good news indeed.