The whole Q1 2009 release (not only Reporting) has been shifted with two weeks and will be available in the beginning of March 2009. We would not be releasing internal builds until then, and we are still considering if we would offer internal builds for reporting at all. They are needed in the RadControls suite, when there is a major showstopper problem in any of the controls, while if there is a major showstopper for Reporting, we would more likely release it as a service pack, since it is a single product.
Thank you for the understanding.
All the best,
the Telerik team