A few hours ago, Elon Musk opened his patent technology for electric cars for use by others. He said that the will not sue anyone who "in good faith, wants to use our technology.
An article talking about this is linked here.
It's likely that Elon Musk expects to see some benefit from working with others who make their own car designs, but its still an impressive gesture, and it is a good sign. Although Tesla has paved the way for electric cars, other manufacturers have not produced their own.
While hybrids are an improvement, they still require gas and emit pollution. Going all electric solves that problem, and producing more of the vehicles will mean that the technology will likely continue to improve.
Although one of his designs was an electric sports car designed to go 200 mph, since then he's produced other types of cars and the technology is steadily improving. The cars rely on a supercharger network. Essentially, electric cars need to fuel their battery even if they don't need gasoline. The network of charging stations now does stretch from one coast fo the United States of the other, but it only recently bridged that gap. Electric Cars are still pricey, but the price is slowly coming down. I consider the technology to still be in its very early adolescence at the moment, but that will change.
Tesla Motors has lost money up to this point, but is hoping for its first quarter in the black this year. The decline of the middle class has made things difficult for Tesla, which cannot as yet produce a version of a car that will sell to people who are struggling to get by. If Tesla does ultimately fail, which is still possible, it will likely have grim repercussions for electric cars. They won't cease to exist, but they could certainly become a lot harder to get.