OK, going to throw some thoughts down. First, a bit about my ereading background so you can view my comments flavoured by my history. I am a long time ereader starting with the Palm V -> Clie -> Handera -> Dell Axim -> Sony 505 -> Sony 650 -> KPW1. I also read on computers and iDevices. I am not loyal to any particular device or format (I am only loyal to Calibre!). My KPW1 is currently jailbroken so that I could modify my fonts/display/collections etc.
I picked up an Aura today and have some preliminary thoughts. The device is much lighter and smaller compared to my KPW1. I could not find a sleep cover to try with the Aura, however, the covers I saw for the HD and Glo looked extremely poor compared to the sleek, tight fitted beauty of the KPW1 cover (it is an amazing cover). I will start researching covers.
The lighting on the Aura looks very, very good compared to my KPW1. Seriously, no blotched/splashed areas of different shades. Did I mention that it looks good?
There is a brighter band at the top noticeable at full brightness (which by the way, is much brighter than my KPW1).
There are about 3 small light spots. They are only noticeable at brightness levels higher than about 75% on my Aura and even then, must be looked at closely to see them. I don't think I will notice them when I read. Overall, the light artifacts on the Aura are way less noticeable compared to the splotchy KPW1 lighted screen (which I have loved to read from this past year).
I took the Aura into the sunshine. The diffuser layer does indeed have some artifacts, but the screen needs to be held off angle to really notice them.When examined, they appear to be diamond shaped...Kobo really brings the bling to ereading! Seriously though, I don't think I will notice while reading.
The fonts look slightly darker on my KPW1. I am not sure if this is because of the screen or not since there are several factors that might explain this:
1. I spent several nights making my own custom font to use on the KPW1 that are better and darker than the stock KPW1 fonts. It only took several minutes to generated a modified Aura stock font using the font menu that come quite close to the custom KPW1 font. This is one area that the Kobo really stands above compared to Amazon.
2. I have not had a chance to load a calibre formated kepub onto the Aura yet and only used a book that was on the device already so I don't know the quality of the formatted book and what engine is rendering it.
3. The lighted Aura screen is slightly more warm compared to the cooler KPW1 screen which may be affecting my interpretation of the font contrast.
I am disappointed that the margins, even when minimized are still quite big. This too may be related to epub formatting and I will explore calibre formatted kepubs with minimal margins or search the forum for a hack to shrink the margins further.
I am also not a fan of the header/footer. I will need to research how to change/hack this. Kindle handles this much better as the header is not seen while reading (only when the controls are triggered) and the footer is also minimal, showing only location/time left to read/etc. I do like the Kindle footer info better than the Aura.
I have not explored Calibre integration, but it can't be more complex than the Kindle's lockdown. I will play with this tomorrow after reading the shelves thread.
So why would I consider switching to the Aura from the KPW1 especially with the upcoming KPW2 Carta device? The biggest reason would be the difficulty in modifying the way books are displayed in Kindles including fonts, margins, justification, line spacing, and collections. The Kindles have required quite a lot of work to develop hacks for and repeatedly break those hacks with each update (java obfuscation anyone?). I expect that the KPW2 will be even harder to jailbreak and customize and may take over a year to develop a significant depth of modifications available for use.