I'm finding that it's so simple to deploy apps to Android that I'm not needing to use the Android emulator at all, haven't been able to figure out how it works anyway (big blinky screen pops up that I don't know what to do with). I just simply deploy the app straight to Android, try it out there, and then uninstall it, if needed.
The whole process (only step 4 and 5 below need to be done for each deployment iteration, after you've done steps 1, 2, and 3 once to set up the deployment environment), takes a few seconds. Here's what I do:
On Android, go to Settings | Applications. Check "Unknown sources". In "Development", check "USB debugging".
Connect Android to your computer via a USB cable.
Start up NetBeans IDE, with NBAndroid installed, as described yesterday. and create your "Hello World" app.
Right-click the project in the IDE and choose "Export Signed Android Package". Create a new keystore, or choose an existing one, via the wizard that appears. At the end of the wizard (would be nice if NBAndroid would let you set up a keystore once and then reuse it for all your projects, without needing to work through the whole wizard step by step each time), you'll have a new release APK file (Android deployment archive) in the project's 'bin' folder, which you can see in the Files window.
Go to the command line (would be nice if NBAndroid were to support adb, would mean I wouldn't need the command line at all), browse to the location of the APK file above. Type "adb install helloworld-release.apk" or whatever the APK file is called. You should see a "Success" message in the command line.
Now the application is installed. On your Android, go to "Applications", and there you'll see your brand new app. Then try it out there and delete it if you're not happy with it. After you've made a change in your app, simply repeat step 4 and 5, i.e., create a new APK and install it via adb. Step 4 and 5 take a couple of seconds. And, given that it's all so simple, I don't see the value of the Android emulator, at all.