[tomsem]

I have both devices (Nook STR and Sony PRS-T1) and would unreservedly recommend the latter, even if wireless library lending is added to Nook STR.

Nook STR effectively has no web browser, PDF support is inferior, and it has no landscape viewing (to mention just a few things). Sony works well with Dropbox, lets you easily look up terms on google and wikipedia, has better annotation features, you can zoom entire pages to view and pan around images or tables, it saves reading options on a per-item basis rather than per-device (really nice when you need to make adjustments for one book but don't want them to apply to everything). With Nook, I have to constantly reset reading options for each thing I'm reading as I switch between them, or else tolerate a less optimal reading experience (e.g. drop caps that aren't formatted properly, etc.).

Unlike Nook (and Kindle Touch), only 'swipe' effects page turn. That sounds like a limitation, but actually makes touch gestures less ambiguous and more efficient and less likely to respond to accidental touches. For example I can usually lift up a piece of lint off the screen with my fingertip by touching it, and without locking the screen first. Hyperlink navigation (single tap) works better since it can't be confused with a page turn gesture, or a selection gesture (tap and hold). And the Sony keeps track of every reading position established in a book, so you can always follow the 'breadcrumbs' back to where you were, and it is trivial to move back and forth between locations as you would with a web browser. On Nook, the 'take me back' button goes away if you navigate away from the initial landing page, so it is easier to get 'lost'.

Nook is better in some respects but I think Sony is a better reading device overall, and it is likely to remain that way throughout their respective life-cycles.

Nook will probably need to expose the web browser again if it is to support library lending, but we'll have to wait to see if browser functionality in general will be available, and indeed, to evaluate how well library borrowing works. Note that some library books are only available in PDF format. Without improvements to Nook's PDF support (specifically ability to crop on the device, and landscape viewing), these will not be very workable on Nook, whereas on Sony they usually are.

One consideration is that Sony will not read books from B&N currently; if you a B&N account with a library there, you won't be able to read them on Sony. There's a possibility that the next release of ADE will allow you to load B&N books onto Sony (which is not supported by the current version of ADE), but that's far from certain at this point.

Though Kindle library borrowing integration is very good (and provides option to read on any device linked to your Kindle account, with sync and annotation backup), I prefer using Sony because of the generally richer formatting of ePub and the better reading options (including ability to read PDF, better navigation options, etc). I do all my 'shopping' on a computer browser to populate my 'wish list' and then Sony can easily access that. By contrast, Overdrive hosted web sites don't detect when a Kindle web browser is being used and they have not created a good web experience for Kindles to use; the assumption is that you are using a computer browser to do Kindle borrowing, which is certainly a lot easier to deal with. It's possible to borrow using Kindle only, in a pinch, but not very pleasant.