The data environment is a wrapper around ADO -- it helps the developer to drag and drop tables, etc., when building the app, and keep coding to a minimum. As with many of these types of fields, it is only really useful if you end up developing an app that looks an *awful* lot like the apps that MS intended it for... my own experience has been that my needs outgrow the data environment capabilities pretty quickly.
The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts. - Bertrand Russell