I visit MobileRead's Amazon forum
multiple times a day—every day—but rarely post. I'm usually looking for Kindle news and to see if there are any questions I can help with.
One of the reasons I don't post there often is because I have a Kindle Keyboard. Most of the questions these days are regarding the newer devices, which I'm not as familiar with.
I also view other areas of MR daily (especially News and General Discussions), mainly to keep up with what's happening with devices and ebooks. I'd comment more often in those forums but often find that either (1) what I was
going to say has already been posted and I don't want to sound like a parrot or (2) I'm not well enough informed about the subject to voice a thoughtful opinion or contribute in a meaningful way. I do find many of the discussions interesting, though.