So, apparently some Cataclysm stuff got leaked. Blizzard may or may not have wanted this to happen, but I think that's beside the point right now. I just thought I would share my 2 copper on the subject.
What I have seen of Cataclysm looks awesome. I am really excited about it. I can't wait to play a worgen, or take Kelesaria to Hyjal, or fly around Azeroth taking way too many screenshots. Some of the class changes make me go 'squee' (hunter pet stable changes? o heck yes please). Some of them make me go 'meh' (don't mess with my beacon, dangit. And I love my trees /sadface). But honestly, you know what?
It's not here yet.
As fun as it is to see new stuff, and plan what I'm going to do first, and all that, the expansion is still a long ways away. It's just now hitting alpha testing. It still has beta after that, and then who knows how much more tweaking before it comes out. And before all that, I still have alts to level (the rogue and warlock will be 80 before then, I swear :P), gear to heroic-farm for, RP stuff to do, and a new raid to hope that I can get into. Kel's guild hasn't faced Arthas yet. My horde alts are still wasting away on a server I don't want them on anymore. There is just too much to do right now.
I haven't clicked any links in Panzercow's blog post. Yet. I might later, but really, I have too much fun stuff going on now, to get too worried/excited about stuff that could be several months away.