Astonishing New Additions in the Bible

I have been reading some more of Hitchens' God is Not Great and I am surprised by the surprise that Bart Ehrman has on the New Testament and Hitchens use of this. When talking about John 7:53-8:11 Hitchens says:

Many years after C. S. Lewis had gone to his reward, a very serious young man named Barton Ehrman began to examine his own fundamentalist assumptions. He had attended the two most eminent Christian fundamentalist academies in the United States, and was considered by the faithful to be among their champions. Fluent in Greek and Hebrew (he is now holder of a chair in religious studies), he eventually could not quite reconcile his faith with his scholarship. He was astonished to find that some of the best-known Jesus stories were scribbled into the canon long after the fact, and that this was true of perhaps the best-known of them all.

It goes on a bit and concludes with a quote by Ehrman:

Overarching all this is the shocking fact that, as Ehrman concedes:
The story is not found in our oldest and best manuscripts of the Gospel of John; its writing style is very different from what we find in the rest of John (including the stories immediately before and after); and it includes a large number of words and phrases that are otherwise alien to the Gospel. The conclusion is unavoidable: this passage was not originally part of the Gospel

Shock horror. What I find shocking is not this discovery of these additions, but the fact that Ehrman only found this out when he attended "the two most eminent Christian fundamentalist academies in the United States." Hight school Christians find this out when they open up any English translation of the Bible and read the footnote that is included with the passage. Also the first quote implies there are many cases like this in the New Testament (and that John 7:53ff is the best-known of all the Jesus stories), which is not true. Hitchens doesn't mention it in his chapter on the New Testament but later in the book he makes this passing comment, again leaning on Ehrman:

The New Testament is itself a highly dubious source. (One of Professor Barton Ehrman’s more astonishing findings is that the account of Jesus’s resurrection in the Gospel of Mark was only added many years later.) 

What I find astonishing is that this is phrases as one of Ehrman's "astonishing findings". Again, like John 7:53ff every English translation footnotes this for Mark 16:9, some even include headings stating it is not in the original or they put brackets around the whole passage. In 1871, before book titles were catchy John William Burgon wrote a book called the Last Twelve Verses of the Gospel According to S. Mark Vindicated Against Recent Critical Objectors and Established. Hitchens couldn't even attributed this finding to Burgon as back then he was responding to other people about this topic. In Burgon's book he even cites Eusebius (300-340AD - Brugon's dates) who way back said that the ending of Mark is not found in all the copies available. It seems Ehrman was a little late in discovering this astonishing finding.

Hitchens laments the fact that there are no textual studies performed on the Quran (I'm not sure if this is true or not), but when textual studies are performed on the New Testament to work out what was in the original for some reason this is deemed to show how inaccurate it is, rather then showing that their findings make it more accurate.

So what does this mean? Hitches use of the New Testament is a bit dubious so when he moves to talk about the Quran, which I have very little knowledge of, I wonder if he is doing the same thing with that text as he did with the New Testament. For example, when talking about how each word in the Quran is important and shouldn't be translated and how the Arabic language itself changed over time he makes this observation:

To take one instance that can hardly be called negligible, the Arabic words written on the outside of the Dome of the Rock in Jerusalem are different from any version that appears in the Koran.

I have no idea if this is true or not, but I wonder if something as public as this has not been dealt with by a Muslim in say the past 400 years and if Hitchens is just skipping over that fact.

Related Links
Which God & what about Jesus? - Some other thoughts I had on the start of God is Not Great