I don't think there is anything wrong with the 700. The poor reviews were the product of so many people wishing for so much from the new 700 that anything short of a cure for cancer, world peace, and universal prosperity would fall short of expectations.
The new unit is beautiful and the controls are better placed IMHO than the 505's controls were. As I remember, the 505 was panned when it was released for everything except the new screen and the 500 before it was panned in almost every review by the mainstream press. Even the Amazon Kindle -- as far as we know the largest selling e-ink reader in the US -- has been widely criticized on all fronts for everything from its controls to its plastic body to its restrictive format offerings. No reader is perfect. No reader will meet the needs and expectations of everyone.
Yes, some if not most of the MR reviews of the 700 have been critical of the unit. Many of these reviewers were expecting the second coming and got only an excellent electronic reader. Sure a lot of the features can be improved; but, improved at a cost. As it stands, the 700's configuration is a hit in the marketplace -- it has set a new price/performance point that others must meet to stay in the game.
People will read the negative review points and then decide if thy can or cannot live with the issues raised. Some of the issues are not important to some people. Others may be show stoppers. This way, when someone looks at one of the new 700s they know what others have said and they can make their own decision. They do not have to worry later, "Why didn't I think to check that out before I bought." They can buy with a clear mind.
When I bought my Sony PRS-500 over two years ago there were many negative things said about the unit. I looked at it and the buy decision was made within five minutes (including the time required to get my wife to go along with the decision. [In fact, she was the one that said, "Go on and get it. You know that you want it."])
So enjoy your new unit in good health and do post about your experiences. We do want to hear from both sides.