News.com confirms that Transitive Technologies is, in fact, the technology behind Apple's Rosetta PowerPC Emulator for their upcoming Intel-based Macintoshes.
Jobs reportedly confirmed Transitive's role in a New York Times interview, but in general, Apple has been very quiet about their Transitive's role in Rosetta. Of note, Jobs' keynote speech on Monday gave no mention to the startup.
It appears Transitive's technology can provide 60-80 percent performance of native software based on real world experience with SGI. Some analysts, however, have doubts about the performance promises.
First mention of Transitive came in July 2003. The most accurate and earliest rumor about Transitive's use by Apple came as a Page 2 news item in February 2005:
...there is evidence that Apple has had special internal seeds of Tiger which support [Transitive's technology] for the x86 platform. Beyond allowing Tiger to run on x86, perhaps more significantly is the potential to also allow existing Mac OS X applications to be run on the x86 (PC) platform without recompilation.
Apple, of course, is not offering Mac OS X for the PC, but instead offering Intel-based Macs.