Not to disappoint him you will need the 3GS. This has a slightly better camera and Video capture. also has a built in compass.
The 3G is still a superb phone and at the moment cheaper.....
The IPhone is actually very very good. It has some shortcomings but not as many as a lot of other phones....It will complement his mac which is something to consider...
Ultimately it's your wallet that will decide.....
