A Google user
This book marked an inflexion point in our understanding of biology. It gave a coherent explanation for the data unearthed by countless scientists who found fossils of species no longer seen on earth. All of this data was numbingly complex and magical until Darwin placed it in a reasonable logical framework. A hundred and fifty years ago he was able to collect enough data to formulate this cohesive theory while leaving the door open to modification if later findings showed any serious flaws in the theory. In the subsequent century and a half the data has grown tremendously and no significant flaws have been found. The theory of evolution has now been verified beyond the pale of doubt for anyone who puts forth the mental effort to understand the theory. To have this monumental, prescient work available to anyone on earth with an unfiltered internet connection is a tribute to humankinds progress from the dark ages of only a few centuries ago. Google's contribution to this effort is significant. Any flaws in the process such as copying the fingers of the copyist in the forematter I can easily tolerate while the major effort goes toward getting all the worlds information available online.
A Google user
A strange experience. One of the seminal science books of all time, well-written (and read by an Englishman who sounds like a contemporary of Darwin), but so outpaced by current science that it's almost laughable. His theory is so powerful, amplified but not superseded by progress, that its tenets are part of everyday life and thought, and to hear him struggle to explain and support his notion of natural selection - "descent by modification" - is almost amusing, as he goes on at great length about breeds of dogs and how bats, but not frogs, populate remote islands. It's an absolutely incredible thought experiment for which has has almost no direct evidence - Mendel's explanation of inheritance followed publication of "Origin" by less than a decade - but his monumental effort seems quaint in the age of genomes. Incredibly brilliant no matter the era, and as brave.
A Google user
Definitely, the intro is biased, you may have read it. Darwin did not "show" that species evolved. He was guessing based on what he admitted was not enough evidence. It's an interesting idea, but not exactly what happens.
Darwin's theories are being challenged now more than ever. The book has little more to offer than an interesting perspective.
It is, however, well written and easy to understand for the people it's written to, other biologists of the 1900s.