As I promised, a new version of Fraqtive is available. It has a completely new generator engine with support for SSE2, multi-core processors, different variants of fractals and many optimizations for almost real-time user experience. Also the user interface has been completely redesigned and rewritten using Qt4 to make Fraqtive available for both Linux and Windows platforms.
Note that this is still a beta version. Please test it and report any problems to the forums. The program is under active development, new releases will be coming soon. For now only the basic features are implemented, but it is already functional - take a look at the Fractal Gallery for some samples of its capabilities. I hope you will have as much fun using it as I had writing it :). Enjoy!