I have both...and I use my ipad much more than the phone, though when out and I need to check on something, that little iphone comes in very handy. Use it to snap pics and send along to others....send email when out, text if necessary. At home, I have a laptop and my ipad....use the pad more than the laptop, it's just easy to carry around. Only have wifi on my pad at home so my phone is used when out and about. Changing to ipad with 3G would change my data plan....got unlimited right now.
Before I had my ipad, that phone was another appendage...
Now, at home, I'm thinking of getting a holster for the ipad.....