The Nineteen Eighty-Four debacle, when Amazon thought it was a good idea to retrospectively delete a title from users' hardware, is just one illustration of the psychosis that overtakes corporations when they realise what they can do with DRM - and they couldn't have alighted on a better title. Why yes, you can absolutely do that. But what the technologists didn't underline to the suits was that it wasn't necessarily a good idea to do it.
Because of the DRM lock-up, the only e-reader I'd consider buying right now is the Irex Technologies device (although I'm not going to get one because this stuff just isn't ready yet). It's more expensive but it's not made by Sony and not tied to a single bookstore. The Plastic Logic e-reader is aimed at the same market: professional users who need to be able to download any PDF and not just stuff bought from an online bookstore. It's possible to get regular PDFs onto the consumer readers, but it involves a bit of work with software such as Calibre.
Transferring books between e-readers is where consumers learn to loathe DRM - you can't unless you have software to strip out the protection, which is not always going to work. So, you find on blogs and forums the common complaint of how people have spent tens or maybe hundreds of dollars on e-books but, because another family member has snaffled the old device, they cannot move it to their replacement reader. Lock-ins work for a while but never long-term.
If bookstores shifted to a subscription model then it might make more sense for consumers to deal with DRM. But, given that very few books get read twice, subscription is hardly going to be popular with publishing houses. It makes most sense for textbooks but the publisher in these markets expect to collect $50 a time for each recommended course book. How likely are they to give that up in exchange for a lot less a month? OK, they 'lose' some sales to the secondhand market but that's why frequently recommended text books get updated to new editions every five years or so.
As people can easily get through several bonkbusters on the average beach holiday, again publishers are going to be wary of letting their best-selling gold-leaf embossed titles go for part of a $20/month subscription when they can get $10 or more for an individual title that barely lasts a few days. Having said that, there might be room for an Emusic-like subscription service where independent titles and those from major publishers that were otherwise destined for the remainder bin can go.
Subscription is the model that makes most sense for the hardware makers but it's hard to see publishers accepting it if they don't have to. The only way they will get involved is if a company with a much stronger position in distribution wants to make it happen or if it can convince enough independents that they will get more exposure if they get involved.