I am genuinely interested in why you think pope Francis has far more effect. There has been many popes in the recent past, how many people even remember their names? Pope Francis is trying to change some policies which might have a larger impact, but we are yet to see that. I would argue that Snowden's revelations are more unique and had an impact similar to 9/11.
There are an awful lot of people that care passionately about what the leader of the Catholic Church - notional membership 1.16Bn - is saying whilst being pretty indifferent to the US government having the ability to intercept their communications (or unsurprised that it's the case) even once you'd explained who Snowden was and why his revelations mattered.
It's not just the US who is intercepting communications, it's at least the Five (plus) Eyes signatories.
Also, you can't have it both ways and say Catholics care passionately about the Pope but surveilled citizens are too jaded to care when comparing the effects of the two. How many Catholics are indifferent to the Pope, care passionately about governments surveilling their citizens?
Everytime you visit a GA enabled site, it sends back some information to the Google servers including url, referrer, time spent etc. Google can use this build up a history of websites you (this is not linked to your Google account, more like an unique id) frequent and show targeted advertisements.
In this example no government oversight would probably work much better. If a carrier starts opening your mails, they would lose their customer base and other services would come up. Also, you could probably stipulate this in the terms of service so that you can have a legal recourse if the carrier violates the contract. With government intervention, all carriers would be subject to government bullying, legal or otherwise. Which scenario would you prefer?
I think it's been shown many times that the depth of consumer considerations of technical and ethical issue is about as deep as a puddle. Most of people simply have neither the background nor time to understand them, and simply assume that whoever's on top is doing things right.
You should optimize the common path, not the edge cases. Most of the time the user would be benefited (cached content = faster load) from using CDN. On the other hand, CDN being unreachable is not a very common scenario, so it is acceptable to be a little slower.
I don't know if the offer was reasonable or not, so I am not going there. But the "value" of such start-ups are often their user-base, not the product or the technology itself. Can someone else implement a similar idea? Absolutely. Would they be able to get all these users? Probably not.
Spark's major benefit comes from storing the intermediate results in-memory instead of storing it in HDFS as Hadoop does. Let's say a certain query needs to run 3 mapreduce jobs A, B, C one after another. In Hadoop, there will be 3 hdfs reads and writes. With spark, there will be only 1 hdfs read (before launching A) and 1 write (after C is completed). In spark, the output of A gets stored in RAM which is read by B and so on until the final write.
The DAG used by spark represents how one job/partition of data depends on another job/partition and what methods (e.g. filter) need to be applied on the parent data to get the child data. This is useful when a node goes down and that portion of data has to be recomputed. Note that users can choose to persist some intermediate results to hdfs to avoid recomputation in case of failure.