here is a head to head comparison between both of them
http://www.pcworld.com/article/199844/iphone_4_vs_droid_x_a_headtohead_c...

i personally prefer the iphone but ive also owned an iphone for the past couple years since the first one came out... i absolutely love it!!!

I have considerably more experience with the Droid (Applications of Embedded Systems allows us to program one) and I have liked it a lot.
My limited experience with the Iphone has not been nearly as pleasant

Droid is able to open more websites than the iPhone, and it does not look like apple is working towards modifying their phone to allow those websites. iPhone is more fragile, and hard to replace. Droid is more durable, and has better warranty, and outer shell