1) I think Tesla will be able to manufacture cars with ranges comparable to the Model S in the near future at a price tag below $50k. I even believe that in the near future a car comparable in performance and luxury along with range will be in the sub 50K range.
I mostly believe this because of how early in the era of electric car technology we are in right now compared to the internal combustion engine era. Many technologies follow an exponential curve in performance, quality, lowering of cost etc. over time. However, at a certain point the curve flattens out. As an example, look at how much the top speed of travel by humans increased from the creation of the steam engine all the way to the launch of the space shuttle. Humans managed to perfect the technology and it grew at an exponential speed. (think of small improvements of train technology over time for a hundred year, then rapidly followed up by the introduction of cars, planes, jets, then space travel in a much shorter period of time).
When you compare this to internal combustion engines, they are much later in their evolution than electric cars. This suggests electric cars are in for a long period of exponential growth, while internal combustion engines are closer to the flattening of the curve (which may still be a long way off anyways.)
Additionally, you have to look at the fuel costs. Oil is expected to continue increasing in cost. It's in higher demand than ever before, it's becoming harder and more expensive to extract etc. Meanwhile, electricity can come from many sources, including solar which is developing at an exponential rate and could start to bring the cost of electricity down in the near future.
Now, your question concerned the price tag of the car, not the ownership costs. However, this is actually relevant to the ownership costs. The rising cost of the fuel can inject uncertainty into the market about cars that run on fossil fuels if the price of those fuels get too high. This can do two things 1) it can increase the cost of capital for traditional car companies because banks are unwilling to lend to a manufacturer of cars with high operating costs, and 2) it could create investor doubt and bring down the stock's price. If either of these things happen for a sustained period of time then it could create an ugly feedback loop for a manufacturer. If 1 or 2 happens and they have to raise the price of their product, then the market may begin to doubt the manufacturer more (especially if Tesla continues bringing down its price tag).
If the traditional manufacturers get caught in a spiral with their traditional engines then they may have to quickly develop electric alternatives. This will likely be fairly tricky. First, they lose part of the brand they have invested in for their traditional line cars (and their trademarks are some of their most valuable assets). Second, they will likely have to abandon traditional internal combustion drivetrain technology that they have already invested in but not recouped the profits of (although they shouldn't fret too much about sunk costs and focus on moving forward). And third, most importantly, if they want to make a quick transition that can at least restore faith from the market, they will likely have to license technology from companies like Tesla (bringing Tesla's cost down while increasing the costs of the traditional competitors)
Finally, one of the biggest costs in a Tesla is the battery. I haven't read about the cost of the battery for a couple years, but I remember reading that the Roadster's battery cost about $40K, and that the S uses the same battery (or at least battery technology). I assume the cost has come down a bit since then, but regardless, the party is likely the most expensive single part of the car. This is extremely relevant because many actors have an interest in producing more efficient batteries (Cell phone companies, Energy Companies, The Military etc.). All these mean that more companies will be putting pressure on the market to develop more efficient battery technology and to bring the cost down.
2) Can't speak as confidently about this because I haven't heard about Tesla's racking up that many miles yet.
However the two things I would consider are 1) operating costs, and 2) legacy costs. As I mentioned before, the price of oil is going up, while the price of electricity is more promising. This means that the cost to the consumer of operating a combustion engine increases, and could offset the increased operating expenses from failure of Teslas in real conditions. As for legacy costs, just look at the history of American auto manufacturers vs. Asian manufacturers. One of the reasons the Asian manufacturers were able to undercut their American rivals was because they did not have retired workers living off pensions. They had lower legacy costs. This is true for Tesla, just as it was true for the previous Asian manufacturers. Of course pensions and unions are no longer anywhere near as important as they were 30 years ago, this could still bring down the lifetime cost of a vehicle from a manufacturers perspective. This means that fuel costs can offset reliability costs from the consume perspective, and legacy costs can offset the reliability costs from the manufacturer perspective.
3) I honestly have no clue how far into development any of these companies are for their own electric vehicles. Honestly though, how much of their capital can they devote to developing electric cars? They probably won't throw the kitchen sink at the problem. Thus, if they are only directing a percentage of their resources to electric cars, then their electric car divisions may only have the same amount of resources as Tesla does. Thus, the only advantage they have over Tesla is brand, but right now given the Tesla hype, it seems brand is in Tesla's favor anyways.
Also, other autos getting into electric can help Tesla by bringing the cost of batteries down, and by spurring the development of a national charging network (And hopefully better cafes along the highway for us to wait at while our cars charge).