We used to do invites based on whoever was available around raid time, with officer discretion used to decide who has to sit out. Obviously this turned problematic in the long run, since no one would know who is going to the raid before the actual raid time, and being a fairly large guild where we had both active and less active players, problems arose as there were no clear rules on what basis players were actually invited to raids.

So, we decided to remove the less active players from the equation and limit our raiding team to around 60 active players. Harsh perhaps, but in hindsight the only right decision we could've made without recruiting enough people to run 2 raids at the same time, which would've just brought a different kind of headache altogether.

We have a static amount of raid spots for each class for every raid, the total amount of players in each class usually being 2-3 more than the raid spots. We then have class forums set up for each class where only the players of that class + the class officer have access. Class officers put up the upcoming week's raid schedule 3 days prior to the next raid week. Players then post their availability, and the day before the new raid week class officers make a list of participants from their class for each raid on the upcoming week.

Class officers try to maintain a fair rotation, so that in the long run all players get to do about the same amount of raids. Of course, the regulars who are always around tend to end up with more raids done than those with more limited availability. Also we tend to use as static a line up as possible for learning encounters, with the best players usually getting priority(assuming the encounter is not quite trivial to learn).

The system has worked very well for us, players know in time the raids they are going to participate on and the whole rotation system is more conversational than just a cold sign up list, as the class officers are always 'close', and players can sort any problems with them. There isn't any kind of competition for raid spots, as players know that it's up to the class officers to make sure that the rotation remains fair.

GCR/TnT has class leaders, and they handle the rosters for each week's raids. We think it's easier for one person to worry about the attendence issues of 7-10 people rather than 70-100. Has worked pretty well so far, though we still get the occasional roster drama (he gets to raid too much, i dont get to raid, why can't I go to bwl, blah blah blah.)

Though lately, we've run into issues regarding attendance in MC because of DKP caps (that's our best guess). As one of the rogue class leaders, our class certainly has no shortage, and I know several of the other classes don't (shaman, warriors). However we've run short on druids and warlocks (hence why I brought my 60 warlock alt out of the mothballs) frequently, and occasionally priests too.

It seems most of our raid roster in MC lately is alts, and we have people switch back to mains to help secure a solid balance in the raid.

I found the 2nd post by Gurg very informative as that is entirely the same situation we've run into, only we haven't been able to field 2 groups for MC yet. We went through a stage where we had a semi-permagroup where we set up veterans, but to prevent the inevitable sniping of team B's players, we had almost fully split within the guild. It turned out that we needed to recruit a lot more people to make a full second team, so we ended up merging back into one group.

Strangely enough, when there were once 60+ people wanting in the 40 slots, now we have trouble filling out the MC raid because it's all alts and none of the mains want to come if they have no dkp/items in sight due to caps.

For new instances, it's pretty much controlled by the class leaders. The individual classes know who are the vets and who have the gear. Each class handles invites differently based on needs. For instance, rogues generally have 5-6 max vet rogues signing up for BWL, so it's almost a no-brainer as we often take 6. Warlocks on the other hand have < 5 sign up for most raids, and we take what we can get on raid day. I know some other classes have pretty strict rotations and such to make sure people get their raid time, and we usually sub people in/out for each boss based on DKP/Item need/wants.

We do two systems; one for learning, one for farm. Both have semi-weekly signups, because we don't have defined offdays.

Learning raids, priority is basically at the discretion of the raid leader, although people who don't signup aren't likely to get invited, either. MTs and DKP officer get an autoinvite.

Farming raids, no one gets an autoinvite, and it's strictly based on signup priority (via classes, obviously - first 5 mages, first 5 rogues, etc., or whatever's needed class-wise for that raid.)