Personally don't see how even being two feet away affects your WiFi signal that bad. I have not seen one out of maybe 20 Nexus's show signal strength that bad. Now it was lower then other devices, but not by a whole lot. I personally feel that some times these signal conversations are highly exaggerated. Only because I have had hands on with too many of them. Again guys stop going by amount of bars, and always go by decibel of signal strength. Remember that the Nexus S has a different system of bars then other devices. In reality it is a lot more accurate then other devices.
However on the note of 4G, yeah I can agree with you some what there. Only because it does seem to suffer from lower speeds, but I was able to pick up 4G signals where the EVO 3D, Epic and EVO 4G could not. Yet the speeds were slow. Also remember that VZW is switching to tiered data, and even what it's at right now is 5gb, that they claim is unlimited. With all the things we stream on our devices today, it is easy to go over even that 5gb. Best example I can give. Listened to an entire album on Music beta on my Nexus S, and checked my data usage and it was over 1gb. I'm sure Netflix, Hulu and many other streaming applications will suck data on that pace as well.