Both the iPhone and Pre are nice phone. Both phones are great for what you're looking to do. The biggest difference between them is their respective carriers. I know a lot of people who'd love either phone, but aren't itching to change carriers for a specific phone.
As cool as the iPhone is, I definitely wouldn't leave Sprint for it. I've been a Sprint customer for almost 3 years now and I've never had an issue. They also have great deals for smartphone plans. I have the entry-level Simply Unlimited plan, and I don't know how I got by without it. I get unlimited everything except for anytime minutes (which I don't use much of anyway). After paying for insurance for the phone (which is very worth it), my monthly bill comes to about $75.
I've had friends who're on other carriers, and even with phone insurance, they still have to pay extra money (like $50) to get their phone replaced. I could stab my phone with a sword, bring it into a Sprint store, and they'll replace it for free.
Different carriers aside, the Palm Pre really focuses on integrating your phone with the web. For instance, having your contacts have more than just phone numbers. You can access their social networking profile, their IM screen name, their email, their phone number.... They also put a lot of work into multi-tasking which the phone does pretty well. Running Pandora, while browsing the web is now doable, as well as typing an email while talking on the phone, and other things. Another area where the Pre is very polished is the gestures. It's easy to use once you get the hang of it. In case you can't tell, I'm a fan of the Pre.
The iPhone has a lot going for it. It's not a super popular smartphone just because it's made by Apple (well, that's part of it,
). It's easy to use, has a ton of available applications from the iPhone app store, it's an iPod touch as well as smartphone.... It's also not the very beginning of a new platform like the Pre. The iPhone might seem a bit less bugggy and more polished. Not to nag about the Pre, but it is the first phone. with version 1.0 of a brand new platform, so ti's bound to not be the Godsend of a phone like Palm wants you to believe. It definitely has the potential, but even I (a huge fan of the Pre) would probably sit this one out for a while to see where it goes.