Rubbish Hardware
I did point out in a comment to the blog post announcing the tablet specs that it's hardware (specifically the screen) was letting the tablet down. This has been the case with most WebOS devices - the screen resolution always seems to be lower than the current standard when benchmarked against Android (forget Apple, they literally sell people overpriced and underspecced hardware every day, due to their cult status). Which is a bit rubbish when you want a phone or tablet to read PDF programming books (with the source code formatting retained).
Shame, 'cos it would have been nice to have a strong competitor to Android (Apple - we'll tell you what you can and can't do with your own device - aside).