[mgmueller]

One unit per post.
I start with my newest addition, Barnes & Noble nook.

Pros:
- WiFi. I can't shop directly on nook in B&N's webstore. I have to do this on my PC with VPN. But then I can download from my library directly onto nook. Very convenient.
- Softroot and already active developer's scene. I don't need those applications. But it's nice to see similar tools as on iRex iLiad before.
- Clock. In the top right corner you see a clock. Permanently, whether you're surfing your menus or reading a book.
- Registration via WiFi. In the former firmware, you had to set your unit's internal clock, to being able to register. Now, in V1.2, you simply set your timezone and can register via WiFi - whether you're in US or outside.
- PDB format. Another proprietary format. But it has been available long before nook. I've had about 150 on my PC, which I bought for my Palm Pilots and couldn't use anymore. Since V1.2, the metadata (author's name, book title) for most of the eBooks is correct.
- Touchscreen. Of course it's just a gadget. But it's a looker and I prefer it over Kindle's 5-way-stick.
- Various fonts, even user-replaceable. I don't really need it. But my tests have been quite impressive. Way more difference than just changing font size. Reminds of "Kindle font hack".
- Metadata in books from B&N seems perfect. I hate it, if I legally purchase books and from the very same source, sometimes even within a book series, I get different naming conventions (book title in capital letters, first name and last name of author switching places, ...). In some bookstores, up to 1/3 of my titles has some kind of inconsistency. Amazon is better than average. But B&N so far seems benchmark: 70 books, not a single one did have any mistake!
- Personal screensavers and wallpapers. Another gadget, not really necessary. But a nice add-on.
- ePUB. You don't have to purchase from B&N (although B&N is absolutely fine). nook can be registered in Adobe Digital Editions without any problems.
- User replaceable battery and Micro SD slot. The Micro SD slot is a bit hard to reach (memory expansion solved best in Sony units), but usually you won't switch cards too often.

Cons:
- No cover included. Not even a pouch. It comes in a very rigid plastic box, which could be used for transportation. But that box is extremely oversized and not for briefly and quickly taking out your reader.
- Only a few covers available. It's a relatively new unit. I'm absolutely sure, in 2 months we'll see beauties from Noreve and others. But right now, on Amazon and B&N, I only found "standard" covers. I don't like the straps to fix a reader, so nothing available for me yet.
(But I'm lucky. My Sony 900 came with a case logic hardcover. It's that huge, that even nook fits into it.)
- Amazon seems to have way more actual books available. Couldn't find about 1/4 of the books I've been looking for - all of them I've already bought for Kindle (Percy Jackson series for example, which right now even makes it's film debute).
- Housing is "tapered". It's very elegant. But there's one strange "flaw": If you look at the unit from the bottom (looking onto the USB port), the left and right side aren't in a right angle, they are diagonally ( _| vs. _/ ). For me, it doesn't rest as conveniently in my palm as iRex 800, Sony 900 or others. (Some readers I simply like to hold without cover.)
- No landscape mode. Very strange - landscape helps a lot and all the other readers have it.

Summary:
nook certainly is a looker. I find it a bit more appealing than Kindle 2. I still prefer Sony 900's design. But given the price difference (nook = $ 259, Sony 900 = $ 399), nook is absolutely "cool".
Like all the others, nook doesn't have any "outstanding features". It's not a "must buy", if you already own Kindle 2 for example. But it's certainly very tough competition for Amazon.
Personally, I rank it (for now) #3 of my 14 units. #1 being Sony 900 and #2 being iRex 800. Both are way more expensive, so nook would be my suggestion for budgets below $ 300.

EDIT: PDF capabilities:
nook doesn't have zoom, just the usual reflow. For "professional" PDFs, it's only an average unit.