I am only confused about one thing at the moment, which after glancing through all the replies, I can not see a definitive answer.
Originally Posted by Blizzard Entertainment
You may also not join someone else's raid if they have defeated a Heroic encounter.
I am hoping this is just poorly worded on Blizzard's part, because if this is what they actually intend, this will only cause problems.
EXAMPLE: Your guild is doing a 25 man heroic raid. 30 guild members were interested in participating, but obviously only 25 can be in the raid at one given time. You are asked to sit out, and you are not saved to any raid ID or bosses. The raid kills the first boss on heroic. A raid member has to leave for whatever reason.
QUESTION: Are you able to join the raid to replace him, or are you shit-out-of-luck?
The way Blizzard has worded this phrase implies that once a raid has defeated an encounter on heroic, they would be required to have the exact same 25 people to continue, without being able to even swap in guild members who are not saved to anything. Again, I really hope that Blizzard just mis-worded this. Being required to use the exact same 25 people to complete an entire raid instance over the span of multiple days will cause massive headaches even for the most coordinated high end guilds. RL stuff happens, and there is almost certainly bound to be many instances where someone won't be able to have 100% attendance throughout the week. So what, the raid is expected to try and continue with only 24 people?