Read it? Good.
My first reaction is holy shit! I recall that a few months ago WoW.com did a post where they speculated about this happening, but I for one thought that Blizzard would never do it. I am sure that this is going to cause the forums to go up in flames, but I want to discuss this in a somewhat calm manner.
In the interest of full disclosure the vast majority of my raiding is done in 10 man mode. They only 25 mans I participate in is the occasional pug. Personally I find 10 mans much more fun. In 25s I tend to feel like I don't really matter and its much harder to get to know 24 other people than 9 other people. I also like the feeling of importance that 10 man gives each member of the raid. In 25 I rarely feel like my specific performance effects whether the raid will succeed or fail. In 10s I know that at times I have singlehandedly given us the extra boost we need and at other times I have personally caused a wipe. However these are my personal feelings and I know that there are many people who enjoy 25 mans. I think the real question is whether this move will destroy 25 man raiding for those who do enjoy it.
I think that the concern people are raising that this will make no one run 25s is legitimate. I don't think that this will happen, but it is not a trivial concern. In the post Blizzard specifies that while 10s and 25s will drop the same loot 25s will drop more badges and loot per person than 10s, hopefully ensuring that those who enjoy 25s will still run them because it will be the most efficient way to gear up. I also suspect that 25s will retain its position of prestige in the raiding community, along with awarding 25 man specific achievements and titles which will encourage continued participation in 25s. I would suspect that come Cataclysm, if Blizzard sees a precipitous drop off in 25 man participation they might make adjustments to compensate, so lets all try not to get our panties in a bunch before we try it out.
So why did Blizzard decide to implement these changes? While I am sure there will be enormous QQ over these changes, lets also remember that there is significant QQ from 10 man only guilds that their achievements in raiding are always considered less significant. A prime example is that 10 man raiders cannot get the Invincible mount from defeating the Lich King. In the current situation a 10 man strict guild can never compete for a spot among the world's best guilds because the loot they receive is always inferior. I think other factor of the change is to help eliminate the grindy feeling of raiding. Serious guilds run 10 and 25 each week, forcing you to go through the same dungeon twice every week, significantly cutting down on the fun after you have been doing this for several weeks. This move is also a way to assure smaller guilds that they won't be at such a severe disadvantage come Cataclysm when guild leveling and achievements come out. A big benefit that people might be overlooking is that this will help cut down on the run away gear inflation that trivializes earlier content. Currently each tier of raiding has many different item levels for 10 man normal, 10 man heroic, 25 man normal, and 25 heroic, but with the change we will only have two tiers of item levels per raid tier. Ultimately what it really comes down to is that Blizzard doesn't want to punish smaller guilds and those, like me, who just enjoy 10 mans.
Well that's my two cents on the topic, I am looking forward to the blogosphere exploding and reading the many posts that will be sure to come.