1997 GTP 4 Door, ~225k miles

I noticed coming of the interstate off ramp yesterday at a red light that my car was shaking quite noticeably and emitting a "blub blub blub" noise from the exhaust. As I accelerated from the light, it seemed down on power to me.

I am uploading a video to Youtube now of the engine running and the sound coming from the exhaust.

It isn't as noticeable in the video as I had hoped, but maybe you guys can get me started in the right direction.

I will post the link when (if) it ever finishes uploading.

Thanks!