I might have spoken too soon about Zotero the bibliography tool. Although it looks great in Firefox3 when I actually came to use it today after a while of only thinking about writing stuff I discovered that I had broken it. I upgraded to Office 2008 (OS X) a couple of months ago and the Zotero toolbar only works with the previous version of Word. Also in the past when I have been using ISI Web of Science a beautiful little import button has appeared in the title bar when viewing records and just clicking it imported the reference in to Zotero. Now its gone. WoS has gone through a website update this year and maybe that killed it. So I exported all my references from WoS (in several formats) but couldn't get them in to Zotero. I could see how to get references from other bibliographic tools but WoS no way. I'm sure this used to work for me. The excellent forums didn't help me much on this occasion.
I have used Endnote since my PhD, but it has always been very buggy and unreliable on Macs (unlike PCs I believe). I got to a stage a few years ago where it was almost unusable, and I saw no signs of them updating the Mac version. I bought a copy of Bookends, which was great, but decided not to pay to upgrade to the new version 10 because I saw Zotero as the way to go. I still do, but wish it just moved a bit faster. I may have to spend the money on Bookends though as I can't live without a working bibliography tool. Sad, I see so many really good aspects to Zotero, but maybe I'll have to abandon it until the next major upgrade.