http://www.bbc.co.uk/news/technology-13639875
Also, Mozilla themselves are a bit frustrated that people are still using their 3.5 browser.
https://wiki.mozilla.org/Releases/3.5_EOL
Update linksWe need a plan to obsolete Firefox 3.5 as we can't support it into perpetuity. We have been frustrated with our efforts to move users off of old releases and are worried too many people do not upgrade and are on vulnerable and unsupported versions of Firefox.
Internet Explorer | Firefox | Safari | Chrome
Opera is not mentioned... here is a link anyways. http://www.opera.com/
Consistent browser rendering makes web developers happy. Help move the internet forward, or at the very least protect yourself from browser vulnerabilities that your browser vendor has long since patched in their newer releases.