Opera, still the most secure browser.
The only browser to have zero outstanding vunrabilities..
http://secunia.com/product/10615/?task=statistics
Opera users should upgrade their browser software following the discovery of multiple security bugs. Version 9.5.2 of the Windows version of the software fixes seven vulnerabilities, including a startup crash that creates a means for hackers to inject hostile code on certain systems (details here). There's also a fix for a …
Does it fix the shocking bugs in v9.5x though, including one where the download manager routines loses partially complete downloads between sessions? After reading the forums I ended up reverting to v9.27.
The first time I've ever been bitten by the version upgrade thing with Opera as well, and I've been a user since something like v5.
www.theregister.co.uk/2008/07/28/browser_history_leakage/ doesn't state anything about Opera, it states all browsers!
Anyways as a long term user I prefer it and use it all the time and as it saves my tabs close it and fire it up another day to keep all my stuff there.
Its nice and fast (I will admit FF3 is faster) and doesn't hog all my memory
I used Opera for YEARS, but the Block Content feature is not nearly as nice as the adblock plus addon for Firefox, and with the steady increase in 'Malvertizements' Firefox seems to be the safer bet. However Opera is the only way to go on the media center hooked up to my 50" HDTV, it upscales websites better then any other browser worth trying (meaning I never tried Safari as Apple is pure crap).