I bought the droid and got the Eris for my Mom.
The droid is a cool phone. Very capable with lots of apps and other cool stuff. Heck when I'm at home I barely use my computer because I'll just do everything on my phone.
At work, I just sit here, listening to pandora.
If you do get the droid, get all your accessories online. You can get out for under $30 for case, screen protector and chargers. Buying all that at the verizon store will cost you almost as much as the phone itself!
Get a screen protector!! They are cheap and protect your screen. There is no difference in touch-performance.
Check out the Incredible too. I played with one the other day and if you aren't going to be doing a lot of typing, then its probably a better phone.
Battery life is pretty good, better if you turn off the GPS. There is an option to "locate via wifi" which gives you a general location. I use this most of the time since I don't need GPS on a day-to-day basis. Takes up no extra power yet if I need to get a general idea of distance, traffic, etc, I have it. GPS REALLY sucks up battery power so having it off is ideal.
These phones are definitely GREAT when you are in a pinch. If you need to find something at the last minute, this thing will do it.
The eris is more of a phone instead of a computer with a phone app.
Lemme know if you want anymore info. This is my first smartphone and I love it.