the 4g is overrated if you ask me. My wife got a thunderbolt which is capable of 4g, but 99.99% of the times it only gets 3g, its a rare occasion you see it getting 4g. So I would prefer to get the pysical keyboard. I just recently had an upgrade and actually had verizon send me an iphone 4, ive had it for two days and I am miserable. I got it since I have an ipad and a mac, thought it be neat to have all iphone. I am sending it back, getting my upgrade reinstated and waiting for the droid 3 to come out.
The iphone is cool and all, but its sooooo limited on what it can do, the thing i hate the most is it doesnt have turn by turn gps and thats what i use the most on my phone and the physical keyboard is a huge advantage. I can type almost as fast as i do on a computer on a droid with the keyboard and without even looking at the keyboard. on a virtual keyboard you cant do that because its too hard to judge where the buttons are.
edit:
other things i hate:
you have to pay for most apps
your emails do not get delievered instantly to your mail server
seems imposible or very hard to acess non inbox folders of your emails
cool apps available for droid are unavailable for iphone and even the ones that are available, are usually not free.