If it's one thing bloggers know how to do, it's bitch. I've read plenty of blogs talking about the "death of 25 man raids" and from a raiding perspective, I really don't care. Here's how it will play out. If your guild is big enough, you'll probably do 25's unless you have several strong raid leaders that want to fight over who's going to come to their 10 mans. I think the logistics of gettign 2 10 man raids going every week will be more complicated than having 1 25 man. Of course this all depends on the size of the guild in question.
Personally, I love the change and I think a lot of people like me will too. See, Blizzard doesn't really cater to the hard core raiders anymore. Those of us like me, who don't want to raid 4+ nights a week are all cheering the fact that we won't feel pressured to PUG a 25 man raid to augment our 10 man progression gear. That's a huge change for those of us who have other stuff to do on weeknights, like maintain our house and deal with adult responsibilities.
But what will this do with the economy? Well, having one less version of a raid to do every week means less potential gear up grades for players every week. That means fewer gems, enchants and their raw materials being purchased. It also means fewer glyphs purchased when specs are switched. So in general, a lot of crafting professions will have fewer sales once everyone hits the level cap and gets settled into raiding for a month or so. The time before that should be ripe with opportunity to make a LOT of money, so capitalize on it while you can!