Developers now have access to Android version 1.1 for the Dev Phone -- an unlocked Android phone. The new operating system has a couple features that purchasers of version 1 were disappointed not to have included.
New features include support for voice search, and the ability to download paid apps in the Marketplace. The previous version of the phone only let you download free apps, which most developers found quite annoying.
It's important to note that the phone is still crippled in the sense that you can't purchase apps, free or not, that contain copy protection. It's unclear how many apps available in the marketplace have this enabled, but I suspect it's a relatively large percentage.
Some developers have asked about the support for copy-protected apps on developer devices, and indeed there is a limitation you should be aware of. Many developers are concerned about the unauthorized redistribution of their applications, so they make use of the copy-protection feature (known as "forward locking") which prevents applications from being copied off devices. However, developer phones like the ADP1 allow for unrestricted access to the device's contents, making it impossible to enforce copy protection. As a result, the Market application on such devices is not able to access copy protected apps, whether they are free or paid. If you choose to add copy protection when you upload your application to the Android Market, then you won't be able to test it on the ADP1's Android Market client. Your application will always be accessible to users who have standard configurations though, and if your application (whether it is free or paid) is not copy-protected it will appear on all devices, including developer configurations. -- Android Developer Blog
The device will run you about $400, and if you live in a country outside the United States, you have to factor in extra duties and taxes -- anywhere from $77 (Japan) to $198.38 (Canada).