Thanks for the link, Serge. Very thoughtful debate on both sides of the argument.
I don't DNG. If the format gets fully adopted, I'll be sure to convert all my valued files. Until then, I don't see a reason to. I'm an amateur photographer who takes plenty of photographs, but I simply don't have the immense volume of RAW files that professional photographers have. If I were a professional photographer, I might be more concerned about the amount of time it would take to convert years and years of photographs on the eve of the RAW format's obselescence. From what I understand, file formats don't become obselete overnight, it's a gradual process of orphanage as the new format(s) are adopted by users. If I were a professional photographer, I would probably be cautious and archive in several formats to ensure speedy recovery in the future.
If there's a point where I NEED DNG to use the latest and greatest digital darkroom software, so be it. I always have my most valued files at hand, and since I'm not dealing with the incredible amount of photo-assets that professional photographers have, it wouldn't be a problem to convert my files when my Canon 300D raw files become universally obselete. I just think it's a little hasty to jump aboard the DNG bandwagon with respect to the file format's infancy. I'm one of those who is concerned with a possible loss of data through converting files to DNG... if the process can't be fully reversed, and adobe gives the silly option of including the original RAW file in the DNG, I believe it's reasonable to say that Adobe isn't even sure that DNG preserves ALL of the valuable image data. The file format is too young to risk putting all my eggs in that one basket... in this sense, archiving in RAW and DNG is the most safe, but probably not practical in terms of storage costs for most of us... but I think archiving in TIFF is a mistake, because the size of a 16-bit TIFF doesn't have all the data a RAW file contains, is generally much larger than a RAW file, and since it has already been processed with a potentially obselete piece of software (say if you were to access a TIFF ten years from now), you wouldn't be able to use modern software to reap the benefits of the data you discarded in the conversion to TIFF (this argument may or may not be true with respect to the archival potential of DNG... only time will tell, truly)
I strongly believe that the solution to keeping digital photographs usable in the future is simply being aware of the technological advances around you. When your RAW format becomes unusable, archive in the adopted format. I'm always aware of innovations of software around me, and I think that as digital photographers, we should have great interest in preserving our art (In this sense, whether you are for or against *currently* adopting the DNG format, we should agree on this. We all want to access our files in the future). I think this is an active process of working with our files, and transferring specific files from media type to media type puts us very close to what we want to preserve, rather than working to satisfy fears of obselescence as soon as a new format is introduced, working at once to archive them in several formats and lay our fears to rest for several years while they collect dust on expensive hard drives or digital discs in our closets. I fully embrace the concept of a universal raw-type, but I don't plan on doing so until I know all the facts.
I don't believe we can truly say, yet, that DNG contains all the valuable data of all the various types of RAW files, which may be utilized in the future. There might be a universal RAW filetype which is used instead of DNG. Such is the adaptation of technology. Just because Thomas Knoll from Adobe says so-and-so about his DNG format isn't good enough for me.