Can you elaborate on the pros/cons? I think we could have figured out that pros/cons exist between the 2 phones, but it would be nice if you contributed something to the thread.
Me personally I like my iphone but hated the lack of a keyboard. Texting on the screen is terrible especially with large thumbs. I haven't looked at the droid yet, but I'm sure it doesn't have anywhere near the amount of apps that iphone does.
Basically if you need the apps get iphone cause there is no way around it AFAIK. Take droid advice from someone else. My next phone is definitely going to be something like the Palm Pre, iphone style large touch screen with full keyboard underneath. I can live without the apps, but I know some can't.
There's quite a few Android phones with a physical keyboard, like the Sony Ericsson Xperia X10 mini, HTC Desire Z, Motorola Droid, Samsung Moment etc. Though in terms of smartphones, I wouldn't class the Palm Pre's 3.1" screen "large".
Pros with the iPhone is it has probably the best looking screen, great resolution on it, wide range of apps.
Cons is it's propriety, not open source, they're trying to push video calling, but it can only work over WiFi and to other iPhone 4 phones, it's not 4G when it quite easily could have been, in England, the price of a contract for it is a lot more expensive. You need to pay around £60-70 a month before you get the phone for free, otherwise you're paying £200-300 upfront for it.
Pros with an Android phone, wide range of different phones. Not everyone likes a full touchscreen phone, open source, Android Market is getting more and more apps every day, even more so with Android 2.2 as you can now install apps to SD, Android phones competing with iPhone i.e. the HTC Desire gets ranked better than the iPhone 4 in some places.
Cons, harder to develop for. You have to take in to consideration the wide range of mobiles for Android is probably Android's biggest weakness, but standardisation takes time. Google didn't release a spec sheet that all phones must be to use Android, like Microsoft did with Windows Phone 7. The Market is lacking in some areas in terms of apps, but that'll fix itself like I said for one of the pros.
That's just a few simple pros and cons for both. Android 2.3 should bring some good stuff to Android as well. And the increase in Android market share has increased a lot in the last year or so.