I'm rooted...but I'm not going to disagree about rooting versus NOT rooting.
if you are able to get satisfactory battery life FOR YOU...on your unrooted device...and YOU are happy with YOUR phone...by all means do what you want.
I just happen to like the additional control/functionality gained from rooting. I can't shake my ROM flashing addiction...leftover from my WinMo days.
Same reason why the iProducts in my family are ALL jailbroken...because I like to have functionality that the devices are capable of...and not restricted by the Fruit.
the wife will be getting her hands on an EVO or Epic in a couple of weeks...and I'm planning on just rooting the stock ROM on hers...so that in the event she wants MORE...I can set her up with it.