The most important change of this release are the accurate timing facilities which made PearPC faster and allowed us to implement idle-sleep. So PearPC no longer consumes CPU time when the client is idle. Other changes are an SDL port (faster graphics), full screen support for Win32 and SDL and of course a lot of optimizations.
For those of you who don't know, PearPC is an architecture-independent PowerPC platform emulator capable of running most PowerPC operating systems, including Mac OS X.
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Download: PearPC Download Page
News source: PearPC Offical Site