When Latias mega-evolved, I remember putting my 3DS aside, listening to Alestorm's "Sunset on the golden age" a couple times to drown out the sound of my childhood and image of the world crashing down around me, and thinking back on those sweet sweet days where things made sense and mega evolutions didn't exist.
Needless to say, I wasn't a too huge fan of it and it didn't make me too happy xP
I'm still not -too- fond of megas, but I'm perfectly ok with them now.
They're a relatively small part of the game the way I tend to play anyway, and they don't really affect me all that much at the end of the day. It's understandable that they want to try and come up with new things to keep the games interesting and stuff, and that's perfectly fine. I'm just not a too huge fan of this particular thing myself ^^'