I decided it would be fun to make an excel sheet and share it with everyone that will keep track of battery life and usage on your phone. Just plug in the correct units and the data should be created for you.
Download Here: Droid Battery Life Excel Sheet
A few notes - Please read so your results aren't skewed:
1) The data in day 1 are my current results, just to show what kind of data is created.
Data on your phone can be found here:
Battery Level: Settings > About phone
Time Since Unplugged: Settings > About phone > Battery Use > (Located at the top)
Usage percentages: Settings > About phone > Battery Use
Rom Version : Settings > About phone > Build Number
2) Ignore Max Est. Battery Life Average (HRS) and Average Time Left On Battery (HRS) until you have 7 days of data, otherwise the 0's in the columns throw off the numbers.
3) These are only rough estimates, a better data set would include probably a month's worth of data, and if you do not know how to do that in excel, just ask and I'll extend the time frame.
4) If you do not have Microsoft Office, you can download an open source (free) office software here - OpenOffice.org - The Free and Open Productivity Suite
5) Do not record data if you started using the phone with anything less than 100%, otherwise the results will be skewed.
6) I use my phone as an alarm and charge it before bed, so it's at 90% before I actually start to use it. If you fall in this category, toss it on the charger and let it hit 100% (also it will reset time since unplugged), otherwise results will be skewed. We want results from times the phone is used while you're awake.
I hope at least 10 people will do this, it will be interesting to compare our final results. If you want to beautify the spreadsheet or add other data feel free to edit it and post up a copy. I threw this together quickly and just wanted to get the main stats up.