The Android Developer Challenge is ready for submissions!

Some key points about the Challenge:

• The blog post that announced ADC2 was open for apps says "you've uploaded a version of your app to Android Market, you'll need to use a different Android package name for the version you submit to the Challenge". That is a big issue, one that hopefully will be clarified in upcoming hours. From a coding standpoint, this would be an annoyance. However, if your ADC2 entry will wind up being distributed and used beyond just the contest judging, you may run into upgrade issues down the road, as application upgrades are tied to their package name.
• Note that you only have a week to enter. In the original ADC, a rush of people submitted apps close to the deadline, slowing down the process for everyone. While hopefully the ADC2 site has more capacity, you still ought to try to get your application posted hours before the deadline, in case of problems.
• Your apps may be tested on phones you have not yet seen, and possibly on versions of Android not yet available (e.g., Android 1.6). The further "outside the box" you went -- Eric Chu specifically mentioned the use of undocumented APIs -- the more likely it is your application will fail outright with some voters.

If the published schedule holds true, the first-round judging app should be available next week, so you can start examining and voting for applications.

May the best apps win!

UPDATE: Applications entered into ADC2 will not be automatically placed on the Android Market, though the ADC2 judging system and the Android Market share a database. The "share a database" issue is why application packages need to be distinct. But, the ADC2 version of your app will not be used outside of ADC2 itself. Changing a package name in Android is no picnic (change your manifest, move all your source code to the new package, fix up any import statements, make a clean build, fix any lingering compile issues), but you will not need to maintain the ADC2 edition after ADC2 has ended.