7200 won't be too much but you may notice some vibration in the palm rests and perhaps more heat and shorter battery life.
This is totally untrue according to my experiences. My 7200 is exactly the same as my old 5400. Quiet and cool. Only difference is the 7200 is much much faster.
No difference in battery life and no vibrations. I'm relatively OCD about these things and there is no difference. You shouldn't spread rumors around like that. Especially if you've never even experienced it yourself.