EndNote / Pages compatability
1) If you edit a reference in EndNote (say, fix an incorrect journal title), the change does not appear in Pages. To change your references, you must delete and reinsert the reference each time it appears, which is extremely cumbersome.
2) If you edit a bibliography style in EndNote, you must quit both EndNote and Pages before the changed style will be available in Pages. Again, this is far below Apple's stated standards for ease of use.
The issue is not with EndNote, it is an interoperability problem that Pages needs to address. See e.g. http://community.thomsonreuters.com/t5/EndNote-How-To/How-to-update-bibliography -s-on-Pages-09/td-p/6265
For this reason, for anyone writing a paper with lots of references Microsoft Word beats Pages hands down, which is unfortunate because Pages has a lot of other advantages over Word. If you agree, please comment on this post and hopefully we can get Apple's attention.
Mac OS X (10.6.7), Pages '09