Quite possibly the biggest game-changing feature in Android 1.5 is support for homescreen widgets. If you've messed with Widgets on a computer, the idea remains the same for Android. It's basically a quick glimpse into full-featured applications, for example you could post a calendar widget, or a stock widget, or a weather widget, etc. It's always-on and always-updated, pretty darn nifty right? In Googlewords:
When widgets are dropped onto the home screen, they are given a reserved space to display custom content provided by your app. Users can also interact with your app through the widget, for example pausing or switching music tracks.
What's even cooler is that the Android developers blog has an incredibly detailed post showing how to make Widgets and have released the full source code for you developers to learn from. So if you're at all interested in Widgets and how to create them, feel free to click on over.
But yep. Widgets = Awesome. Days like these make me feel good for picking Android.