I know we've gone around this topic in a number of threads, but here's a view of the 'plug thing' from the 'mothership'.
From the Plug-In 2010 conference: http://green.autoblog.com/2010/07/28/plug-in-2010-bill-nye-chelsea-sexton-return-for-public-night-p/
About 34 minutes in, an attendee asked the panel (Chelsea Sexton, Bill Nye, and Jessie Deeter) why we needed to work on a hard-wired yet standardized recharge connection when we've got 100 years of history in this country with 110 and 220V outlets.
Bill Nye: With regard to 220V, here's our problem as I understand it. We in the electric vehicle community (if I can say we and us and you and we)...we cannot kill a single person. Now, I have a few people that I would be more than happy to ah, if they got electrocuted...I mean...it wouldn't be that...I would not be troubled too much. Frankly, I've always wondered, do your bones really light up? You know, like in a cartoon? And so from time to time, in an RV park, recreational vehicle park, someone (and I don't want to generalize) someone might have been enjoying an adult beverage - or two - kills themselves with a 220 plug. That might be Darwinian and all good, right, that are people that make these choices and kill themselves and that's how it goes. But we in the electric vehicle community we cannot have the connector cause the death of anybody. So that's why all this trouble. The connectors are really hard to electrocute yourself with. And I've given it to this one person...I got him drunk but he couldn't do it. That last part's a joke!...is that right Chelsea?
Chelsea: Yes, a lot of this has started from a place of fear, way back when, and at least we're at least at the point of having some standardization and there's even this littlest bit of talk that maybe every charger doesn't have to be hard-wired - and maybe there's some opportunity for some cracks in the fence. But it's absolutely true that we're so interested in doing this in a safe, credible, robust way whether that's infrastructure or conversions or whatever because the technology will be held responsible not only for early efforts to commercialize it but any catastrophic things that happen. And, let's face it, at some point a car's going to catch on fire. At some point someone's going to wreck one and die. This will happen! But the longer we can keep it from happening, the better off we're all going to be. So for now, we've got a simple solution in terms of technology that everyone can agree on, so let's implement it and get some cars on the road! And then we'll worry about, based on some real user data, what we can sort-of relax a little bit about and what we need more attention on.