I did a quick estimate of how many charging locations Tesla is adding by going to
this page, clicking a country, and finding all "coming soon" chargers.
I found that Tesla is adding 398 charging locations in North America, 155 in Europe, 100 in Asia/Pacific, and 4 in the Middle East for a total of 657 added charging locations. Since Tesla's global total is currently 842, Tesla seems to be planning to have 1,499 supercharger locations by the end of 2017.
California is getting the most superchargers out of any region in this expansion, adding 82 new charging locations on top of the 52 already there. Since California will be adding a total of 1,000 chargers according to the blog posted today, there will be an average of 12 chargers per location while the rest of the world will be between 6 and 8 chargers per location.
Tesla's 790 supercharger location network had a net book value of $207.2 million according to the 10-K for 2016 (that includes accumulated depreciation), so a ~1500 charging location network would probably be worth more than $400 million, putting Tesla even further in the lead as far as charging networks go.
Lets compare Tesla's network to Anton Wahlman's description of Volkswagen's upcoming charging network
in this article. Wahlman tells us that Volkswagen will spend $300 million to build 2,500 chargers in 39 states and an additional $200 million for chargers in California, bringing the total to ~4,000 chargers in the US by the end of October 2019. Tesla will likely surpass ~4,000 chargers in the US by the end of October 2017, so they have a two year lead on the closest competition.