I've recently written a broker/display pair of addons (OakInterruptsBroker and OakInterruptsDisplay) to track the cooldowns of your party/raid member's interrupts. You can also set up (multiple if you like) interrupt rotations and announce these as people are interrupting. I feel like it's at a point (I have gotten rid of most apparent bugs, and I think its reasonably usable) where I could use some feedback / bug reports / suggestions from others, so please try it out for me and let me know what you think. You can leave bug reports / suggestions in the ticket system on wowace.
Currently there is no GUI configuration screen, so you'll have to use the slash commands to control the addon. PM me if you have any questions about it (I know I haven't documented everything yet, though the slash commands reference should be complete), but I'll try to do that soon. Hopefully I've made it intuitive enough to use that you won't get stuck with general usage.