First off, although 3G is criticized on the new IPhone with both software and hardware being blamed, the fact remains that it is still much faster than my Treo was... even when the IPhone is on EDGE. I live fairly close to a 3G-enabled tower and receive speeds over 1000kb/s when testing the speeds with a 1MB download test over 3G and around 140-150 kb/s over EDGE. My treo often struggled to break 120 in the same room of my house, which, although it does not sound like a lot actually makes a large difference. The primary reason is that although sustained download speeds may be similar between the devices (with 3G off of course), the treo suffers from much higher average latency times.
Another area where the IPhone blows away the Treo is portable media (Video/Audio playing). Of course you could argue that this isn't fair and that the treo is a business device and that the other is a consumer-friendly whatever, however, everyone likes to relax to a song on the way to work whether it be on a bus, subway, etc. The Iphone, besides offering more storage, also sounds better, and with a larger screen makes watching a movie much more enjoyable (although this probably does not apply to everyone). FInally the integration with ITunes on both Mac and PC blows away the almost lack of native mac support and the mediocre windows support Palm provides. Once again there are work arounds such as The Missing Sync among oters, however, not everyone wants or has the time to invest in such a solution.
Wifi/Web Browsing Not much to say here except that the Palm OS browser is outdated and that although mobile Safari does not provide support for all webpages (Flash/Java), it does a darn good job. Wifi, well... Palm in my opinion just took too long to jump on the bandwagon (I know 800w... but windows mobile isn't my cup of tea)
Although it sounds like I am praising the IPhone a lot, not all is well in the Kingdom of Jobs. First off, the Iphone can not at the time of this writing be used as a portable USB flash drive. All other IPods can and people always carry their phone around... so why not. I know there are apps to transfer data over wifi via FTP among other protocols, however, no usb support exists and support out of the box should be a must. With my Treo it was as easy as putting the SD card into a card reader or using the app card reader is I was really lazy :P or if the PC did not have an SD reader.
Second, the battery life is um.... lacking. I know that it still does better than a lot of 3G phones and I know that there is a lot of battery-sucking hardware in the IPhone, however, the best way to conserve power/get through a day is to kill all the new hardware/software (3G/Location Services/Push). I remember reading another review that the slogan for the 3G version should be "Half the Price, Half the Battery Life). Although I so not see this large of a problem, I miss getting two days between charges on my treo. Of course I was using the IPhone a lot more than I used my Treo, however, the Treo battery ofter used to last 6-7 hours for me while the IPhone struggles to get 4 with 3G off, location services off, auto-lock 2min and puch/fetch off.
There is a lot less for the "power-user" in the IPhone. One of the best examples was when I had wanted to send multiple pictures to a relative detailing part of a trip I was taking. Even in the horrendous VersaMail, I was able to send multiple attachments at once, however, with teh IPhone, you can only send pictures... and one at a time. How about support to email any type of file like the treo had. Also along the lines of email... although the Treo wasn't too great... with the iPhone I have to manually delete each message, there is not mass delete which makes it annoying when I spend precious time downloading mail from forums or lists. Of course I could make filters on my account, however, how hard is it to support a delete all button? The problems also spread to the camera where Apple must have spent more time on the animations than it did on the functionality. There are still other examples, however, I think I got the point across... that although the Treo had its downfalls, I had a lot more control over the OS and the programs within it.
Third party support is still limited. This is only a "Bad" for the time being however, as I am sure we will soon see more and more quality apps being produced. However, lack of support for editing and creating word/excell sheets in these days of mobile productivity is disappointing... Docs to Go did this how many years ago?
Apple has been very careful when releasing the IPhone and later the SDK to keep most of the power to itself. They argue that it is better they are in control of applications, etc, however, a lot of very useful programs I enjoyed using on the Treo will probably never see the light of day on the IPhone, and if the do (Netshare RIP), they will probably be removed fairly quickly. Even programs like Flashlite and other web browsers from Opera and Mozilla will ever stand a chance against the strict rules Apple has built into the SDK agreement.
An so, in conclusion, I love my IPhone and it will be an important part of my life, however, I will still be looking to my Lifedrive for quite a few applications... at least for the time being. I hope that Apple continues to work on some of the bugs still present in 2.0.1 and that the IPhone 3G will continue to grow into a smartphone I can rely on in the future.