I bought a Nook Color for one purpose only: reading technical PDFs. It arrived on Nov 26th and I've used it to read several docs. Here's my review, limited to NC's PDF handling as it handled EPUB and PDF differently. If you want a review of NC's intended main function, that is, as an EPUB reader, there are excellent reviews out there.
The likes:
* Orientation lock.
* Variable zoom. You could use pinch-and-zoom to size the document just right. Another way to zoom was to use the '+' and '-' buttons to zoom in pre-determined increments.
* Zoom setting was kept across pages. This was huge in terms of usability. I had tried some devices, including one that was currently very popular, that did not preserve zoom setting across the pages. Each time you change page, you have to re-zoom.
* Handled scanned PDFs. Scanned PDFs are PDFs whose pages are images. The largest I tried had 750 pages that were scanned at 150dpi resulting in a file size of 170MB. NC handled it easily. There was no slow down flipping from page 555 to the last pages. I read (actual reading) about 130 pages from the document comfortably.
* Ease of side loading. When connected to a computer, it presented itself as two USB mass storage devices, one for the internal memory and the other for the microSD card. There was a directory 'My Files'. You could re-arrange its contents to your liking.
The borderlines:
* If you drag a page (to expose more lines) or zoom out, the newly visible area would appear white for a while. I presumed NC did not do off-screen rendering. How long it stayed white depended on how much of new area NC had to render. With both scanned and non-scanned PDFs, when I dragged my finger from the very bottom to the very top of the screen, creating a very large new area, it took about 1/2 or 3/4 second for NC to populate it. The lag was not noticeable at my reading pace. It became noticeable when I had to pan around, for example, trying to look at a graph at the top of the page when I was almost at the end of the page.
* It couldn't display two pages at the same time. This was useful for looking at pictures that span two pages as usually found in magazines.
* I didn't see any text reflowing. May be it did that only on certain text PDFs?
The dislikes:
* If you switch applications (even something as simple as going to the home screen and choosing to continue reading (by clicking on the upper bar of the home screen)), you'll start at page 1 instead of resuming where you were.
* No bookmarking. There was no bookmark facility for PDF. So before you switch application you need to remember to note the current page number.
* It did not keep track of the last page read. Again, you need to note the current page number yourself. Fortunately, sleeping and resuming the device preserved the current page.
* Did not support Table of Content. A TOC was essential when you have a voluminous PDF.
* No search functionality.
* There were handling problems with some PDF documents. For example this MQSeries API document. If you read from the first page, NC renders it correctly. You can rotate, zoom in, zoom out and such. But if you jump to, say, page 555, it'll go bonkers. If you want to go to the next page, you have to use the go-to-page functionality. Flipping page by swiping or tapping did not work anymore. It also displayed the documents at fit-page zoom level which made the text too tiny to read, and you couldn't change that.
* Did not display Chinese characters.
I returned the device on Dec 3rd. I could tolerate some of the dislikes, but I couldn't stand having to remember the current page number. This deficiency would likely going to be fixed in the future. The development team had been diligent about improving the original Nook, and I certainly could see them putting similar efforts for Nook Color.
There was also news of successful hacking of NC as an Android tablet. May be in the future we could finally load up a proper PDF reader on NC.
I'll probably revisit NC if it gets bookmarking or remember-last-page functionality.
