I've owned a Sony PSR-900 Daily Edition ereader for about a year now and recently upgraded to a Nook Color after seeing it at a B&N store recently. My main reasons for purchasing the Nook Color were (not in any special order): a desire to read at night (this was always hard to do with the Sony ereader even with a clip-on light), color so that I could see comics better (I have a bunch of old Spiderman comics on CD-ROM/PDF), video support, and web browsing.
In general, epub reading is very nice, especially with the ability to change the font to a "nightime" color scheme of white on black, bookmark, etc. I would say that it is superior to the Sony. I tried reading in bright sunlight and after I increased the brightness, I was able to read OK enough for me (I did buy the anti-glare protective screen cover, though). The Daily Edition always had a little bit of glare in bright light because it had a touch sensitive screen on it, so maybe the glare difference is bigger in other e-ink readers, but compared to the Daily Edition, it's comparable after you increase the brightness.
The part where I am disappointed is in the pdf support. Not the general viewing of them, the resizing and auto-rotate are fantastic, but the lack of features, particularly pdf-reflow or the simple ability to bookmark where you are at. This was a real turn-off for me. If you stay reading the same PDF without going to another book, it will remember what page number you were at and return you there. However, if you change to read another book (epub or pdf) and come back to your first pdf book, it will return you to the beginning of the pdf file. This wouldn't be so bad if you could save a bookmark in the book, but you cannot. This caused me to convert many pdf files to epub format just so that I could place bookmarks, etc. (thank you Calibre!). I hope that they add this simple yet vital feature in future updates to the Nook Color. One more comment - the pdf reader doesn't support the nightime-mode white-on-black fonts, either. In general, the Sony Daily Edition handles moving between pdf books much better than the Nook Color because it does remember where you left off AND allows you to make bookmarks. However, the display of the pdfs looks much better in the Nook Color.
I am likewise disappointed in the organizing abilities of the Nook Color. I liked the Sony idea of collections and relied upon them heavily. I had set up Calibre to create my tags as collections in the Sony. I don't have any of this in the Nook Color. The closest thing that I get is organizing books by author or title. I like the idea of "shelves" but if the Nook Color doesn't allow shelves to be created/modified by programs such as Calibre, then it creates a lot of manual work for me as a user. I guess I'll have to get used to using the search function a lot. Hopefully they will open up their shelves in future updates so that Calibre can work with them. The Sony also had a view that let you see all your bookmarks so that you could jump around to different books that you were reading, but the Nook Color doesn't have such a view (I couldn't find one, at least). You can look at recently read books, but if you had bookmarked a book that you opened a long time ago, it is not easy to find it unless you know the book title so that you can do a search for it.
As for comics, the color and sharp resolution make comics look great. Thank you B&N! I haven't fooled around with video too much yet, but I've found some good hints on how to move video there (
https://www.mobileread.com/forums/sho...d.php?t=107571) so I look forward to trying that out soon.
In general, I'm pretty pleased with my purchase, just annoyed at how they treated PDF support. I'm now converting many of my books to epub via Calibre to get the bookmark support that I like, but I wish I didn't have to do that. I look forward to future updates in the software/firmware, and especially look forward to when B&N opens up App development more (next year, I hear).