Hi Brian:
The 1.x branch of ArcGIS Mapping for SharePoint is considered to be feature complete, and current planning has the 1.x versions as the only ones that are supported on the MOSS 2007 platform. Depending on need, it is conceivable that there could be another 1.x maintenance release, but this would only be to address issues in the current 1.x product and would almost certainly not contain additional functionality.
While we would always like to make new versions of a product available to the widest range of users possible, there are substantial differences in the architectures and capabilities of MOSS 2007 and SharePoint 2010. As such, we had to make the very difficult decision for version 2.0 of whether to target a more limited set of functionality that is supportable on both platforms, or target SharePoint 2010 exclusively and provide users on that platform the best experience possible. In the interest of providing the best and most functional product that we can, we ultimately chose the latter.
I can certainly understand your disappointment and hope that this helps you understand why we came to the decision we did regarding platform support at version 2.0. I also hope that, when you do have access to SharePoint 2010, you will give the latest version of ArcGIS Mapping for SharePoint a try.