Anders blog on: SharePoint Manager 2010 Release
A lot of people at the SPC2009 conference asked me about the future of WSPBuilder. Facts are that SharePoint 2010 is under way and the new SharePoint tools for Visual Studio 2010 are going to replace VSeWSS.
Here some conclusions from the SPC2009 conference.
This means that all the current solutions out there for SharePoint 2007 will still need to depend on a 3rd party tool to get the job done.
Regarding WSPBuilder, a new version will be release to support the new possibilities in the WSP package for SharePoint 2010. The new version will still provide support for SharePoint 2007 packages, so bug fixes and added functionality will also be available for old 2007 projects. I plan for that WSPBuilder Extensions will support 3 versions of Visual Studio 2005 / 2008 / 2010 in one MSI packaged.
So WSPBuilder will still be around for a couple more years to support SharePoint 2007. Only time will tell if it will be popular for SharePoint 2010.