Change your Gmail password back, done :-). Sorry, I couldn't resist.
We had a verizon outage in my area yesterday. Restarted my phone and up pops the login box for my main gmail acct. After restarting my phone at least twice a day since this first came up it had to be something with the outage here yesterday..
Thanks for all the help!
Luckily, I stumbled across a way to quickly and easily change your account’s password on your phone.
Simply go to the Android Market on your phone.
You’ll get prompted to enter a password — enter the new password you created for your Google account online.
After you’ve made the change, go back to your home screen
Press your Menu button
Go to Settings
Go to Accounts and Sync
Press the applicable Gmail account
Press Sync Now at the bottom of the screen
This should show that your sync is now working.