In the past we've used several web based raid planners including eqdkp and phpraider. When the in-game calendar was improved we jumped in and tried to work 100% with it for all guild events. It has sort of worked out for us, but there have always been issues.
The major ones being:
No way to declare spec on signup
No management of alts
No management of wildcards or attendance history
Confirmations can't be done out of the game
So I was wondering if there are any raid planners out there that integrate with the armory. I've seen systems where guild rosters are pulled from the armory to keep the player list current. What would be awesome would be a raid management option that allowed the RO to sync the data for a particular raid into the organiser before places are allocated.
With such a system the best of both worlds would be available. We are a casual guild and would like our players to not require mods or website registrations to participate in events, but we have very mature and tech savvy raid leadership who who would like more power than the in-game calendar provides.
I've never done much with organizing addons. I set a raiding schedule for the guild on our website forums and raiders are expected to show up. Paying attention to who is what main-spec and off-spec can be dizzying at times, but you will get the hang of it pretty quickly.