My first impression of the Sony Reader was one of disappointment. I had only seen it in a display case or in the hands of commuters on the subway and it seemed pretty sleek then. But in my hands it felt rather cheap (no more, no less than the Cybook Opus, but the metal finish can be deceptive) and the quality of the display was not as sharp as I expected. Considering the original price difference (however, with a recent price reduction, the Sony is now less expensive than the Cybook Opus!), I was expecting more from the Sony Reader. After trying it out, I found that it had not much more functions than the Opus. Of course, here it is important to precise that the model provided by the library network (as it was for the Cybook Opus) was an older model.
The Sony Reader PRS-600 is larger than the Cybook Opus (6.9 x 4.8 x .4 inches) and is nearly twice as heavy (10.1 oz/286 g). It also offers a slightly bigger Monochrome E Ink touchscreen (6 in.) with similar resolution (same 800 x 600 pixels but with twice (at 8) the grey scale levels). I don't have any details on its processor, but it has only 512 MB of memory (enough for about 350 books, which is less than the Opus, but it can be expended with Memory Stick Duo and SD Card up to 16GB). Its rechargeable Lithium-Ion battery is good for about two weeks or 6,800 to 7,500 continuous page turns (slightly less than the Opus). It supports the DOC, PDF, RTF, TXT, BBeB, EPUB, BBeB DRM text formats, the BMP, GIF, PNG, JPEG image formats and the AAC, MP3 audio formats (that's more text formats than the Opus, which also cannot play audio at all).
The PRS-600 features also includes highlighting & annotation capability (although limited), five adjustables font sizes to improve readability, and a built-in dictionary (2nd edition of the New Oxford American Dictionary). It comes with a USB cable, a cover sleeve, but (unlike the Opus) there is no mention of pre-loaded books. It is offered in three colors: silver, black, and red. Originally priced at $250 CDN, then reduced at $170 CDN, it is now a discontinued model.
In summary, the Sony Reader PRS-600 is larger (but heavier) than the Opus, and has less memory as well as a slightly shorter battery life. However, it has the definite advantage of supporting more text and audio formats as well as having a touch screen. It compares well with the Opus because of its nicer design and the fact that it is lightweight and quite portable (but it lacks the Opus' pre-loaded books and accelerometer). Being an open format device, it is also more versatile than most of the other popular readers (like the Kindle or the Nook, which only offer proprietary formats and online stores) as it can read multiple formats (particularly the Epub format which is becoming the new standard of the book industry) and you can purchase books not only from Sony online store but from any online bookstores.
Basically, the Sony Reader PRS-600 has only two main problems: it has no wireless connectivity (you must be plugged to a PC to download books) and its screen really doesn't look as good as it should (resolution, contrast and a reflection problem under bright light could all be improved; the touchscreen isn't as responsive as it could be [like the iPad for example], there's no contrast adjustment and no backlight to help read in darkness). I might also add that the annotation feature is rather cumbersome to use and the battery is not removable (same problem with the iPad: it is soldered to the board).
Fortunately, since the release of the PRS-600, Sony has considerably improved its line of Reader. In September, it has announced three new models and two of those were immediately available: the Touch Edition / PRS-650 (6 inch., improved touch-screen and 16-levels grey scale, 2 GB memory, 7.6 oz (215 g), $229 US / $250 CDN) and the Pocket Edition / PRS-350 (same but with 5-inch touch-screen, 5.5 oz (155 g), $179 US / $150~$200 CDN; this model seems to have received pretty good reviews). The third model will be released in November: the Daily Edition / PRS-950 (same but with 7-inch touch-screen, .5 pound, and WiFi connectivity, $299 US).
Of course, Sony's Readers might still be more expensive than the Kindle or the Nook but, because of their design, portablility, touchscreen and greater versatility, I would definitely recommend any of them for use in a library environment. However, for a personal use (if you want a device that is more than a reader, like a netbook, and don't mind paying a lot more), my first choice will always be the iPad.
I am still not very enthusiastic with the idea of lending ebook readers in libraries. I know that it is already being done in some libraries in the USA, but I feel that doing so would be looking for trouble. A colleague made the interesting comment that we were lending Dvds without the Dvd player, so why should we also lend the ebook reader? (the point is sound but another librarian found arguments to ridicule his comment -- in french). I guess we should just wait and see how it goes for the libraries who have reader-lending on trial.
In any case, if you have the opportunity to try (or the budget to buy) a eBook reader, you should not hesitate. It is a liberating experience.