Nexus 7 is a fantastic tablet, and it's stock Android, so you don't get any bloat on it like you would with a Samsung tablet or something. No idea on when the new versions are coming though, so just as you said, might be best to wait and see what happens.
As an update, I loaded up the Kindle app on my iPhone, and have had great success reading there. Something about having my phone everywhere has made it really convenient. 10 minutes before a movie started yesterday, I took it out and read a few pages. So now I'm thinking more than ever I need to get a phablet phone! hehe