My husband has the Evo, and I just got the (long awaited) white iPhone 4.
I LOVE the iPhone, and was pleasantly surprised when I realized how long the battery lasts. The Evo sucks battery FAST, but my husband LOVES the phone. Android is definitely a close competitor with iPhone, and each has its pros and cons.
But, frankly, I'd have to say the iPhone ultimately takes the cake. The battery life is excellent, it may not be 4g (which is LIGHTNING fast, if you're in an area that supports it. we are in DC, so it works well here), but it runs super smooth, and if apps are your thing, consider that while Android may have "more" apps available, Apple's apps have to go through an approval process to make it to their app store. Android's don't. My husband says that while there are many great apps for Android, there are thousands that just suck.
One more thing: when I was still considering whether to wait for the new generation of iPhone, or to buy the 4 (either would be my first iPhone), I received lots of advice from people. The one thing I took to heart was that, it's an iPhone, you'll be happy with it, whether it's the newest one or not.