EE 2.2 Add-on Developer Preview
Announced on the ExpressionEngine blog, EllisLab is now accepting requests to be included in the add-on developer preview for EE 2.2. The move allows add-on developers some time to get their add-ons up-to-date with changes in the EE application. This is particularly important has EllisLab continues to improve the codebase and roll out changes that can break third party add-ons.
The blog post from Marcus Neto has all of the information you need, including the steps to apply to be in the developer preview group. While they work on a more formal way to join, the process is manual (file out some info, email Marcus, etc).
Marcus also included a nice technical round-up (courtesy of Greg Aker) with examples of changes in EE2 and why it’s important that add-on developers take part of the developer preview program.
Read the entire write-up: ExpressionEngine 2.2, Add-on Developer Preview