Opera Software releases Opera 11.64 Final for Windows, Linux and Mac incorporating new features, improvements and stability adjustments. If you wonder why your Opera suddenly upgrade from 11.62 to 11.64 skipping 11.63 it’s because 11.63 was thrown out a short while back.
Opera 11.64 does not contain many bug fixes, but it is a recommended security update and it does fix some crashers and a bad nsl bug some people get on e.g Ebay.

Opera Web Browser
Opera 11.6x uses the latest version of the Opera Presto 2.10 rendering engine. The star menu in the address field allows you to quickly bookmark a page or to create a Speed Dial entry. The release incorporates web specifications added up to and including Opera Presto 2.10 core-integration-point 229. For further reference please see: Web specifications support in Opera.
Opera web browser has over 200 million users worldwide while it is not bundled with any desktop operating system. Besides Opera Mini is the most popular mobile web browser as of May 2011, has been chosen as the default integrated web browser in mobile phones.
You can find and download this release appropriate for your platform from links given below:
Note: Opera 11.64 is a recommended upgrade offering security and stability enhancements.