It looks like this week's Thing is going to be fairly brief for me, as I have ruled out Zotero owing to the Firefox restrictions, and having had a look at the 'citeulike' tour, I don't think it's quite for me - although I can see a lot of benefits with regard to writing collaboratively. I think the ability to share articles and references in such a way is great - it just doesn't really relate to anything I do, so while I am glad to have actually found out what it is, I am not going to go any further with it at this stage.
I decided to explore Mendeley instead, simply because I am in the early stages of writing an article for a journal, and consequently have what feels like about a zillion different articles that I'm in the process of reading through, or have decided could be useful in terms of extracting material from. So to find a tool that will help me to keep track of all this is fantastic. I completely agree with Isla - the last big piece of written work I did was my MSc dissertation, and the manual insertion of all the references was something that took me quite literally hours, as I was so worried about making a mistake that I ended up checking them through several times - and nearly losing my sanity in the process!
Mendeley is not only great because I have been able to upload all my PDF articles to one place, but it also will hopefully enable me to create my final bibliography with a lot more ease than the manual job I had at dissertation time. I also love this annotation functionality - I used to have to work from hard copies because I like to highlight/annotate as I read, which you can't normally do in an PDF onscreen. With Mendeley you are able to do this, and then you don't even lose your annotations when you print - brilliant!
While this tool definitely has a lot of potential use in terms of writing articles, or even keeping track of current awareness materials that are particularly interesting, it doesn't really have any relevance to me in my day to day job - nor is it really something that we would be promoting to the fee-earners; simply because this kind of tool is not something we actively use in the corporate law library. I could see great potential for people who work in academic/education libraries, but less so for corporate users. Nonetheless, I am really happy to have discovered this tool - I had no idea such applications even existed!