I definitely think there's a potential issue with buying into an e-book platform where there's a high barrier to switch.
About two years ago, my girlfriend decided she wanted an e-book reader. At the time, you could only get a Kindle online, and she didn't want to buy one without seeing the device first; so we bought a Nook reader (after she played with it in the store).
Over the next year, we probably bought about $2000 of books on it, when she finally got tired of being envious of my Kindle (which I had recently purchased) and I gave it to her.
She ended up spending like three weeks cracking the DRM on all the Barnes and Noble e-pub books she had purchased, so that she'd be able to read them on the Kindle.
Most people wouldn't have done that, I suspect. They'd have just stuck with whatever platform they initially decided on (and had amassed a collection of DRM-laden files with).
My girlfriend got on to the ebook train early, before the Kindle was available in our region, paying ~$500 for a Cybook that reads Mobipocket format files.
A few years later, after amassing a couple of grand worth of DRMed books, the reader failed - and this presented two problems.
The first was that a replacement e-ink ebook reader that would read DRMd Mobipocket files was now impossible to come across, EPUB having mostly won out in the non-Kindle market. The second was that all those DRMd books she "owned" were locked to a broken device ID.
The only solution was the same as in the parent comment - spend a decent chunk of time breaking the DRM and changing their format.
Ironically, this is an advantage of Kindle. The last time I checked, Kindle DRM was relatively easy to get rid of. I didn't research as exhaustively because I wasn't very interested, but it seemed like non-Kindle formats were harder to deal with.
The Kindle format actually is Mobipocket underneath, but with an algorithm layered on top that converts a Kindle serial number into a Mobipocket ID. Needless to say that algorithm has been leaked.
About two years ago, my girlfriend decided she wanted an e-book reader. At the time, you could only get a Kindle online, and she didn't want to buy one without seeing the device first; so we bought a Nook reader (after she played with it in the store).
Over the next year, we probably bought about $2000 of books on it, when she finally got tired of being envious of my Kindle (which I had recently purchased) and I gave it to her.
She ended up spending like three weeks cracking the DRM on all the Barnes and Noble e-pub books she had purchased, so that she'd be able to read them on the Kindle.
Most people wouldn't have done that, I suspect. They'd have just stuck with whatever platform they initially decided on (and had amassed a collection of DRM-laden files with).