I'd be very wary of this format, although I'm happy to report it does seem to be dead in the water anyhow. Dataplay, it seems, uses a proprietary compression format with Draconian "copy protection" built-in. I remember reading about the workings of Dataplay: a write-once format with no editing or copying capabilities, oppressive registration requirements which force you to give personal info to the Dataplay Corporation, etc.
If you search the "General Discussion" forums at minidiscussion.com you'll find plenty of valid criticism about Dataplay. I also clearly recall Dataplay's shameless method of planting trolls at Minidiscussion. Quite unethical, if you ask me.
With all this, is it any wonder the format failed before it ever took off? Then again, Dataplay may have been a scam all along - a way to extract investment money from the likes of Vivendi Universal (who invested something around $50 million in it).
Avoid ANY and ALL formats which infringe on your fair-use and privacy rights (and Dataplay looked as bad as Circuit City's happily dead Divx format). By not adopting them, this is the ONLY way to prevent them becoming the norm.