I've been having a problem with the Kindle app; with one book (of which I'm aware; I don't know if the problem is more widespread), the screen goes to white and is dead. I have to dump the card, restart the app, and the same thing happens. The problem was not with the book, which reads perfectly on the Kindle app on my Touch.
I googled the problem and I'm not the only one. It seems as if closing out all running programs will let the book launch and read successfully, but it's a nuisance. It mostly matters to me in that I've been indulging in a few good deals at Amazon not available in ePub, thinking I could read them on the Touchpad. I'm disappointed to learn that Amazon is walking away.
Don't know if I'll try hacking at some point or not. I'm a technotyro, so I could easily brick it. In a lot of ways, I like the WebOS and I don't really care about most apps, but I'd really like a way to read my DRMed ePubs. Then the Touchpad could be an all-purpose device for traveling.