This module is unmaintained.
Sorry folks. Since I left my previous (Drupal-related) company, I haven't found time to work on this module, and without a strong time commitment I don't believe this is going to go somewhere. The good news is that the number and quality of other import/export modules has increased, so you'll likely find something that suits your needs. (See the next point.) The other good news is that a new module called Rules Transformers takes many of the ideas from this module and sets out to implement them on top of the magnificent Rules module, starting from Drupal 7.x and with an entirely new code base.
Good luck with your quest for the perfect data transformation module!
Upfront note for people researching modules.
There are a multitude of different import and export modules in existence to handle the complex task of getting data from other systems into Drupal. A wiki page has been created in an attempt to focus the efforts of the module developers and provide a handy guide for users looking to make a decision.
This module transforms data.
It doesn't care which data, and it doesn't care how. It just makes it possible to define operations on whatever kind of data, and lets you create pipelines in order to wire up those operations.
This module is an API.
It also ships with a default user interface (Transformations UI), but is designed to be used seemlessly from within your code. It's modular and does not pull in unnecessary code or undesired pages.
This module is pluggable.
It's relatively easy to code new operations, and autoloads any of those when they ship with other modules.
Add operations to your favorite module now, without any impact in case Transformations isn't enabled!
This module is complex (for a Drupal project, at least), and strongly object-oriented.
If you're afraid of classes and objects in PHP, run away now.
On the other hand, Transformation's architecture makes it possible to centralize Drupal dependencies in specific places, which is going to lower the porting effort between Drupal versions, and most importantly makes this thing maintainable at all.
This module can do lots in principle, but little out of the box.
It's equipped to power stuff like import/export functionalities, deployment, or Yahoo! Pipes, but essentially it's what you make of it. Currently there's CSV Transformations, XML Transformations and Drupal Transformations available as add-on modules, extending the set of operations that can be used inside transformation pipelines.
This module is still unfinished and work in progress.
Some parts of the API, and hopefully the UI too, might still change a lot. Don't expect it to do anything advanced at this point. Instead, come and join the project and help to realize its potential! If you want to use it without planning to get involved, you'd better wait for a stable release.
Transformations itself - the API module - does not require any dependencies.
The native user interface (Transformations UI) depends on the Chaos Tool Suite for temporarily storing your unsaved pipelines. It can also make use of jQuery UI for drag&drop functionality, this is an optional dependency though.