[d2viant]

It's horribly confusing to someone who doesn't understand that it's not being rendered by the browser itself. PDF's (especially when rendered inside the browser) break the browsing experience.

Your browser controls stop working as expected, history gets bent, links don't work as expected. All of a sudden you're now working within an Adobe Reader application or FoxIt Reader (albeit embedded in the browser) without even realizing you're in an entirely different context outside of an HTML page.

[ugh]

Links and history work as expected (at least in the browsers I know with native PDF support) and I’m not sure why it is bad that some users might not understand that a PDF document is not a HTML page.

I also don’t know how Scribd helps users understand that better. Seems horribly confusing to me if you don’t follow them closely. (Wait what? The PDF is suddenly a webpage? But sometimes Flash? I can still download the PDF? Why doesn’t it look exactly like the webpage? What’s going on?) It’s perfectly usable, even without a deep grasp of the concepts, but so are PDF viewers inside browsers.

[DougBTX]

The problem historically with plug-in PDF readers was that the Adobe one was very slow. That seems to be fixed now - though I can't tell if the software is better or I just use faster hardware.