"In this review I used the Qt 4 version of Opera 10
alpha, build 4102 (the .tar.gz package), but Opera 10 will be
available using both Qt 3 and Qt 4 toolkits, so you can choose
which one you prefer. I ran Opera in Debian Lenny (KDE 3.5.10) with
all the updates to date.
"Presto 2.2 engine
"Opera 10 alpha is powered by the Presto 2.2 rendering engine,
which, according to the website, should provide 'significant
improvements in speed, performance and security'. Presto 2.2 also
comes with improved CSS performance, web font support, and a score
of 100/100 at the Acid3 test, where Firefox 3.0.5 gets 71/100 and
Konqueror fails. Acid3 is a test page for web browsers which shows
how much a browser follows web standards like DOM or
JavaScript."