This issue is now over four years old, and still has not had anyone assigned to it :-(
Every now and again while working with Jira in my day job, I come across a project that another department is working on which I would like to keep an eye on, then I remember that Jira does not support the ability to watch a project without using a messy work around.
Come on Atlassian, fix it please!
Updated 2021 : note that the above post was originally published in 2009, but is left here for archival purposes. That Jira ticket is now open with Atlassian for nearly 17 years! It makes me feel less guilty about some of the tickets in the backlogs of my teams.