The first taste of the next iteration of the Opera browser is just around the corner. Opera Software is currently cooking a preview version of Opera 10.5 and is gearing up to make available for download a pre-alpha build of the browser next week, a few days ahead of Christmas. Details are scarce at this point in time, but from the little information that was shared with the public it appears that the next generation of Opera will apparently be designed to offer as much horsepower to end users as possible.

“While everyone is off for Christmas vacation, the desktop team is working hard on preparing a nice holiday gift for Opera users. On December 22nd we will release a 10.5 pre-alpha. We'll keep it a surprise for now, but the keyword is: speed,” revealed Opera’s Huib Kleinhout.

Opera Software first mentioned that it was shifting resources onto the project building Opera 10.5 at the end of October 2009. In this regard, the Norway-based browser maker has moved extremely fast, if approximately two months later it is just ready to offer the first development milestone of Opera 10.o's successor. And while Opera has never been accused of lagging rival browsers in terms of speed, with version 10.5, the browser maker takes on Google Chrome and Firefox, just like Internet Explorer 9. Microsoft demonstrated a preview version of IE9 the past month at PDC 2009, indicating that it matches Firefox 3.6 Beta in terms of JavaScript performance, and is only twice at slow as Google Chrome Beta.

Opera 10.5’s focus on speed automatically means that the browser will also kick up a notch the level of JavaScript performance. Users should in this context expect a new version of the Opera ECMAScript/JavaScript engine. At the start of this year, Opera Software revealed that it was working on the successor of Futhark, a new engine under the moniker Futhark. Carakan is expected to be at least twice and a half (250%) faster than Futhark, currently featured by Opera 10.0 and Opera 10.10 with Unite.

Jens Lindstrom, Opera developer, revealed in the past some of the strong assets of Carakan:

“- a register-based bytecode instruction set. In a register-based machine, instead of a dynamically sized stack of values, there's a fixed size block of them, called "registers".

- compilation of whole or parts of ECMAScript programs and functions into native code. This native code compilation is based on static type analysis (with an internal type system that is richer than ECMAScript's ordinary one) to eliminte unnecessary type-checks, speculative specialization (with regards to statically indeterminate types) where appropriate, and a relatively ambitious register allocator that allows generation of compact native code with as few unnecessary inter-register moves and memory accesses as possible.

- in the new engine, each object is assigned a class that collects various information about the object, such as its prototype and the order and names of some or all of its properties. Class assignment is naturally very dynamic, since ECMAScript is a very dynamic language, but it is organized such that objects with the same prototype and the same set of properties are assigned the same class.”

Opera 10.0 and Opera 10.10 are available for download here.