"Raids require a lot more work and can be substantially more complicated. Just because it's possible to farm Naxx or ToC in pugs right now doesn't mean the entire community can do it -- but the entire community can do random heroics (for the most part). There is also the problem of reforming the raids and finishing them at a later time."
Normally I would not even address such comments as this one. It's time to set some things straight to shed some light on this stone age way of thinking. Blizzard WANTS players to play together more. This is why leveling has only been raised to 85 in the next exp, tier 9/high end items are obtainable through heroics, and the biggest of all cross realm LFG tool. In fact the LFG tool is the first step to a LFR tool that auto ques raiders that met raid leaders specifications. Raids are no more complicated than heroics. Look, raid bosses usually have 4 mechanics to them.
1. Strong debuff that can wipe the raid
2. Fire/lava/acid that you should not stand in
3. Movement of raid group to avoid damage
4. Get on adds then back to boss
THAT IS IT! Nothing more complicated an average player could understand over vent in about 5 minutes.
Players have a hard time showing up on the same server for a raid. Cross realm would present no further problem than same realm raids. How about set the raid ID as a key and once the raid leader rejoins the raid que previous raiders can now use their raid key to join at a set time. I bet Blizzard developers are smart enough to put something like that in place.