First, if you're thinking that a week isn't enough time to form a valid opinion, I disagree. I disliked the speed, lack of features, and touch screen tech within minutes of using the M90 for the first time. The only reason I didn't write the post that day was because I wanted to make sure I wasn't jumping to conclusions.
Before I give a good recommendation, an expensive ereader like the M90 has to show some redeeming feature that would make this a better purchase that an Android tablet (the Asus eee Transformer, for example). I cannot see any.
The M90 takes minimalism to an art form. It's white with a strip of silver trim around the face. On the front it has 4 touch buttons on one side of the screen and an optical mouse on the other. There are no card slots or buttons on the side or top edges, and on the bottom edge you will find volume buttons, headphone jack, power button, USB port, and the SD card slot.
It uses a 9.7" Pearl E-ink screen, and under the hood it has Wifi and a Wacom touchscreen. It's running Linux on an 532MHz Freescale CPU.
The touchscreen is my first complaint. I know this may sound silly, but I've really come to appreciate the IR touchscreen found on the Nook Touch, Kobo Touch, and Kindle Touch. Those screens don't require a stylus and they offer the same clarity as a Wacom touchscreen.
I cannot help but feel antipathy towards a 9.7" screen that requires a stylus. That is something that was acceptable in past years because it was the best option available (if you wanted to use an E-ink screen). Now that there are better alternatives I do not see a reason to use Wacom anymore. I mean, would you really like to have to use a web browser if it required a stylus? I would have tolerated this last year but not now.
I've played with the M90 for a little bit each day, and much to my surprise the battery was dead this morning. I know that I charged it fully before using it, which means that it only took 5 days to drain it. That's just not good enough.
I said in my earlier post that the M90 was slow. I'm sticking with that assertion. As part of writing this post, I set up and took the lead photo. Just waiting for some simple things like the onscreen keyboard, the browser, or the menu was incredibly frustrating. The lag on this is simply unbelievable and it is unacceptable in 2011.
And no, I'm not comparing the speed to an LCD tablet. I think the M90 is incredibly slow when compared to almost any of my E-ink based ebook readers.
The M90 comes with software similar to that found on its smaller sibling, the A60. In addition to the reading app, it has a note taking app, scribble app, web browser, and one game (Sudoku). It also has the same impressive annotation options as the A60.
Unfortunately, it also has the exact same menu, software design, and over all feel as the older and smaller ereaders. That's a problem because the older menu is designed for a 6" screen. The larger screen on the M90 opens up a number of options that aren't being exploited. The M90 doesn't feel like any work was put into the software. In fact, I've found a bug or 2.
BTW, while I like to talk about the annotation features, they're really nothing special anymore. Sony has released an equally feature rich ereader (T1) as well as on with as nearly as large of a screen (950). To be honest I think the PRS-950 is actually a better choice for several reasons (speed, touchscreen, cost and features).
If at this point you still plan to buy a M90, please ask someone to hit you over the head repeatedly. This is truly not the ereader for anyone. I believe that virtually any device currently on the market would be a better choice.
This is a $380 ereader that I believe is best suited to be the guest of honor at a target range.