Pendulum, oh my fucking god, Pendulum.
They used to be so, so good, but now they sing poppy shit for the masses, which is mostly pre teen scene kids.
Example A - When they were good.
Example B - When they became shit.
There are a few song on their new albums which are okay (Visions is an awesome song for example), but it's mostly pure, and utter crap.
I wish Pendulum would go back to their old Drum and Bass stuff.
Also, PJ Harvey, she used to be the queen of rock, but now she's lightened up her voice and became the queen of...folk?
Old - Dark, very anti pop, grungy kinda music.
New - Light hearted, hard to listen to, folk music.
...yeah, I'm not a fan at all of her new stuff (I personally think she went downhill after stories), but I still think she's awesome though.