The first project I worked on at Microsoft was Data Access Pages. I started off owning the Access/IE 5 relationship and working closely with the IE developers to make Trident a good platform for designing web apps. In Office XP I was responsible for all of the designer enhancements including multi-select, grouping drop zones, etc. Unfortunately, that work never caught on with users.
Access 2007 users can continue to run data access pages but we will not supporting creating new ones or making design changes. You would need to use Access 2003 for those activities. If you are using WSS lists the new SharePoint Designer and the native WSS authoring experience is the likely replacement for thin apps.
Looking back, I learned a lot about what it means to design great features that customers love. There were lots of great ideas in DAPs that we used in updating forms and reports--the notion of layouts was inspired by some of the tabular control movement work we designed in XP. In the end, DAPs suffered from a number of reasons:
Over the long run our users will benefit more from the team focusing on our core competencies: forms and reports. I'm really excited about the new WSS list support, filtering, interactivity in reports, layouts make design so much easier--The list goes on and on. There are lots of cool new scenarios opening up with Access 2007.