There is a wealth of information in the wiki:
http://code.google.com/p/phantomjs/wiki/PhantomJS. Should you have
more specific question, please post it here as a new thread (don't
hijack this one!).
This 1.4 release is just a minor update. If you are happy with 1.3,
then I recommend to stay with 1.3.
Beside various bug fixes, two important new features of this release
are both contributed by KDAB engineers (many special thanks!).
First is the web server support using Mongoose
(http://code.google.com/p/mongoose/). Details about the implementation
can be seen in https://github.com/ariya/phantomjs/pull/172. After
testing it for a while, personally I still consider it as an
"experimental" feature. There are still features and polishes needed
before it can be really smooth and useful for various purposes
(WebDriver, Capybara). Thus, please consider this release as a way for
you to give feedback and influence its further embedded web server
direction, should you want to use it for the related purpose.
Second is the support for building with Qt 4.8. Since Qt 4.8 was not
released during the development, this is still in the form of build
script + patches. For the details, check out
https://github.com/ariya/phantomjs/pull/173. With the patches, you
will get extra goodies as such as pure headless (no X11 on Linux),
improved PDF support (based on tweaks from
http://code.google.com/p/wkhtmltopdf/), and remote inspector. I plan
to fold all these features into PhantomJS 1.5 as we integrate Qt
source tree (http://code.google.com/p/phantomjs/issues/detail?id=226)
step by step.
Thank you!
Best regards,