I'm disturbed about the people who purchased books, but didn't download them, before the books were yanked....isn't that illegal? I know they keep a record of when/if a title is downloaded...if you purchased it, and didn't 'take possession'(download), surely they have to either make it available to you or refund your money? I'd definitely send some emails.... Also, did I understand correctly that some people can't access DRM books they've already downloaded?
About deDRMing...best I can recommend is--google is your friend, and there are a number of threads that explain how to go about it for the various formats. Use the Search, Luke...er...yeah

. Not having to worry overmuch about the format of an ebook before purchasing it is very liberating! Plus not having to worry that formats won't be supported down the road....
The only downside of the ereader drm is keeping track of outdated credit card numbers; I'd imagine it would build up after a while...