I doubt it will get anywhere this late in the game unless they also wake up the DoJ and get on the case of Apple, Google, B&N, and Kobo in regards to DRM. And DRM is only half the issue. Kindle books can only be read on Amazon-offered hardware and software, unlike ePub which can be used by Sony Reader, Kobo's devices, and B&N's devices. So it's not just DRM, it's file format too. And I've railed for years about Amazon not going with ePub but have accepted they've basically won, although now with iOS devices in the half billion, they have some actual potential competition. (And I say potential because iBooks is an optional download, made that way by Apple to thwart EU regulators who otherwise would have quickly awakened to a Windows-MSIE type bundling restraint of trade issue.)
I've had good luck using Calibre to convert EPUB to MOBI for use on Kindle. In particular, I had a subscription to the digital edition of "Analog" from B&N for a couple of years, and Calibre got all of those issues nicely onto my new Kindle Paperwhite. ("Analog", at least from B&N, does not have DRM).
Lack of epub is an issue. Amazon's format, in addition to being proprietary, is a weird and hard to deal with (due to historical PalmOS-related baggage). Also, I believe that the epubs tend to have more future-proof data (cleaner HTML, etc).
However, I have no sympathy for these publishers on the DRM front. If they want DRM then they can pay the piper (i.e. Amazon/Apple). I personally don't see a lot of merit in this lawsuit as long as Apple, Amazon, etc. allow users to load their own third party books onto the devices. (And you can make your own books for the devices.)
Nobody is stopping them from selling books for the iPad/Kindle, lots of publishers like O'Reilly and Baen do. They're just stopping them from using Amazon/Apple's DRM without paying Amazon/Apple for the privilege. The same thing happened with music, and the industry eventually decided to drop the DRM. (And I think Apple is still selling a decent amount of music without it.)
The bookstores are asking the court to issue an injunction prohibiting the publishers and Amazon from “selling e-books with device and app specific DRMs,” while also requiring the big six publishers to allow independent bookstores to directly sell open-source DRM e-books.
It sounds like they are asking the courts to order some kind of "open source DRM" that they can use. If they don't want to use DRM, Kindle and iBooks work great today. If they don't want anyone to use DRM, then the article is misrepresenting them.
The article refer to the fact that these ebooks are limited to the Kindle and that is part of the lawsuit. I don't believe it is too late to happen; the DoJ seem to always wait for someone to complain before they act, so it might be what was needed.