I haven't been on these forums in awhile but my battery life has been up and down.
I just wanted to fill people in on a three things I have tried that I haven't heard of other people trying much. My battery goes all day and then some now WITH location services, notifications, fetch, wifi and bluetooth.
While combining my emails into iCloud, turning of most Facebook Notifications and turning off Calendar Notifications aren't complete solutions for everybody, they have dramatically increased my battery life.
Here is what I did to "combine" my email accounts to limit the number of accounts syncing to my phone:
1. Turn on iCloud and create a me.com email address.
2. For Hotmail:
Log into MSN/Hotmail
Click Profile Name in Upper Right
Click Options
Click Mail
Email Forwarding under Manage Account
Type in your iCloud @me.com email address
Save
3. For Gmail:
Login to Google
Click the gear for settings in the upper right
Click the Forwarding and POP/IMAP tab
Add a Forwarding Address
Confirm using the email sent to your iCloud account
Select Forward a Copy of Incoming Mail to: (Select your iCloud email)
Save Changes
4. On the iPhone:
Go to Settings
Go to Mail, Contacts, Calendars
Add Account...
Other
Add Name, Address, Password and Description (Hit Next)
Under IMAP (how I did it) enter your me.com email address for the incoming mail server.
For the Outgoing Mail Server enter the host name, email address and password you would use to send messages. (For hotmail, it would be smtp.live.com and, for gmail, it would be smtp.gmail.com).
Click next... You will get all of your email through your me.com email and you will be able to send email from the account you chose above.
I hope this helps some people... I have got answers from many others and I felt obligated to share something that has helped me double my battery life. Even after, doing most of the other fixes on here, I was losing 10 to 15% battery life with light usage in two hours off the the charger... Now I am losing ~5% in that same time (have class every morning so my usage is pretty consistent).