Essentially all of the PvE changes together seem aimed to disincentivize 25s, is there some reasoning as to why 25s are no longer being encouraged?

Our goal through Wrath of the Lich King was that players could choose 10 or 25 as a personal preference. We think we missed that mark though. Because 25s still provided more powerful rewards, it felt like that was the “real” raiding, and 10s were what you did on off-nights, or if you just couldn’t stomach the logistics of recruiting or pugging 10 more players. We know there are a lot of players out there who just prefer to raid 10s but felt like we didn’t deliver on our promise to let them just raid 10s. The Cataclysm model is to let players raid 10s or 25s as they see fit. There are advantages and disadvantages to both raid sizes. The larger raids can feel more epic, yet the smaller ones tend to have less loot drama because there is less competition per item that drops. The smaller raids in some sense are more hardcore, because there are fewer opportunities to include novice raiders or folks who just aren’t carrying their weight.

We understand that changes like this can cause social upheaval and we didn’t make the decision lightly. The community was similarly concerned when we removed 40-player raids (and we literally did remove those; today we’re just offering an alternative to the larger raids). We think there is a non-trivial audience of players who prefer the 25-player raids and we’re going to continue to support them. We tried many different raiding models in Wrath of the Lich King with regard to Heroic modes and lockouts, and rest assured that if we don’t like how the 4.0 raiding game evolves that we will revisit it for 4.1. #