I did some quick searching and found nothing concrete pertaining to my question.
That is, Are you experiencing better or worse battery life with 2.1 installed on your droid, compared to 2.0.1?
[Note: I have installed 2.1 using the FAQ at the top of this section of the forum]
With all that said, I think the battery life on my droid has gone down after installing 2.1. For example, today I took the phone off the charger at 8:30 am. [8 hours later] I've used the phone for voice calls for a total of 9 minutes. According to the power manager, i'm at 30% battery life and the voice calls used 23% of overall battery.