So I'll chime in. REdiculous has some valid points. His argument basically boils down to, "The Leaf is not for everyone". I think we'd all have to agree with that. It is suitable for some people, which is the best that can be said for any car. I'd find it alot more useful than a Ferrari if I was not allowed to sell the Ferrari to buy a fleet of Leafs. In our household, we have two cars, one is an SUV and one is a compact car. I ride my eBike most days, but drive if I need to carry someone else or if it is raining cats and dogs. Neither my wife or I would not exceed the range of a vehicle with half the range of the Leaf on virtually any workday and very few weekends. However, we do a lot of home projects and would need something that can pull a small trailer anyway. So we'd probably keep one gas burner, but we have two cars anyway.
Consider that over 60% of trips are taken for destinations less than 15 miles from home and that of those, the overwhelming majority (around 85%?) have one person in the car. From that point of view, the Leaf may actually be overkill for most trips. But as REdiculous points out, it will not be good for all trips.
I am not a battery expert. There is probably a fundamental limit on the practical specific energy capacity of a battery, but I don't know what it is. Even if the range for a personal vehicle is substantial, it seems unlikely that commercial transport will be powered by batteries. So in the best case we will probably have a mix of biofuels for commercial transport and e-vehicles and biofuels for personal transportation.
Lastly, I think the contention that hydrogen powered vehicles are a non-starter is a bad one. If you've never heard John Turner from NREL speak, you should try to catch a seminar if possible. If you are going to use hydrogen though, I would suggest using a fuel cell because it overcomes the thermodynamic limits of heat engines. Also, you need to come up with a sustainable way to produce hydrogen, since practially speaking, hydrogen is an energy carrier, like a battery, and not an energy source. That is my day job, actually. Back in the 90s, I think, (maybe early 2000s?), a fuel cell and hydrogen tanks were installed in an SUV (don't remember which one). No interior space in the vehicle was used. The vehicle was driven 300 miles up the coast of CA on one fill-up. And by the way, about half of hydrogen produced today is actually used by the petroleum industry in hydrocrackers and hydrotreaters. Go to: http://utkstair.org/stair/seminar_topics_fall2010.html and scroll down to the links for John Turner's presentation. I think the fuel cell car is mentioned in that presentation. That page is the seminar schedule for a graduate program I directed last academic year.
PS: I've driven a Leaf. It is a very nice car. Even if you could build your own for a slightly lower cost, you'd have a hard time matching the quality of the final product.