We have just migrated from FogBugz to JIRA. In FogBugz, when viewing a list of issues (i.e. the Navigator in JIRA) you could see the last comment made on the issue. This was very helpful for our developers and they've asked if it can be added to JIRA.
Basically, it would just mean that in the area where you can customize your Navigator columns you could add a 'Last Comment'.
Is this something you can incorporate into a future update? I've attached a screenshot showing you what I mean.