Not to continue an argument, but just throwing this out there. Last time I stayed at Shades of Green (in December 2011) there was no bus going to EPCOT, only buses to the Transportation and Ticket Center. So when we left EPCOT at night, we had to take the monorail to the Transportation & Ticket Center, and then get the Shades of Green bus there. I don't know if thats how it always is, but I remember being slightly annoyed because it seemed as though it took longer to get to the parks that way, especially the Magic Kingdom since Shades of Green isn't far from there anyways.
About the tour groups- I've been during cheerleader season, only Brazilian groups, and I think they could go either way, really obnoxious/intrusive or polite/friendly. Some of my issues with tour groups are not the fault of the group members, but the people running the groups. On certain rides, (I've noticed this at Test Track a decent amount of times), the groups will all go into the single rider line, and then at some point during the boarding process the person leading the group will stop and talk to a CM about letting the group go together. I don't know if someone in the group got nervous and didn't want to ride alone or what, but thats annoying in my opinion. It is clearly stated that certain queues are for single riders, and if the entire group is just following the one person guiding them, its that persons responsibility to make it known that they will not be able to ride together. This really isn't Disney's fault, and for all I know just being an onlooker may not be the group members faults either, but this is one thing that bothers me.
I agree with the poster who mentioned that a large group of uniformed/matching people can make you feel a little uncomfortable as well. Not so much when its a family reunion or something when its about 20-25 people at the most, but when theres 80 teenagers in neon colored shirts and a couple of chaperones its understandable that one might become uncomfortable. This is especially true if I'm at WDW by myself, which happens a couple of times, especially while I'm there with my grandfather who naps during the day in the room. I don't want to be the one random person who gets stuck in the group of 80 matching shirts.
The singing/chanting is rude in my opinion. If its a couple of little kids singing a song, then whatever, its a big park, its outside, that little group of children is not going to bother anyone. Its just the size of some of the tour groups that makes it annoying. When there is so many of them singing/chanting, its just... well... unwanted.
The fastpass issue, really isn't an issue to me. I would much rather one person from the group get 50 fastpasses than the whole group wait in the fastpass area. If a ride runs out of fastpasses, yea its crappy, but its not the end of the world. If I want to go on it I'll wait in line, I really don't think its that big of a deal.
The whole one person holding a spot in line and then the whole group comes and meets up with them is annoying, but that really isn't limited to tour groups. A family or group of friends could very easily do the same thing. Its overwhelming when its a larger group that may/may not speak English when you explain to them that you were waiting and they should wait at the end, but this problem does not occur with tour groups alone.
If I see a tour group going in one direction, I usually just go in the other. If you don't want to deal with a group that large, thats probably the best thing to do. Though the solution to the problems would probably be to split the groups up, though again that is not in Disney's control. I don't think a group of 50 should be walking around the park all together, because thats where most of the problems arise, if they were broken up into groups of 5-10, it would probably be much less of an issue.
-end rant- lol.