Several readers have noted IBM's announcement that they will be releasing a PowerPC-Linux based reference platform.
IBM says it will make its blueprint easily accessible to a wider range of developers by charging a low price for it--allowing the company to pit its PowerPC-Linux combination as an alternative to operating systems like the Palm OS and Motorola's processors or Microsoft's Pocket PC software and Intel's Xscale processors.
Of interest, the reference platform will not seem to have very strict requirements (no logo is required, no specific screen size). According to the article, IBM hopes to encourage small businesses and even individuals to be able to purchase the design for use.
The significance of this announcement in the relatively small PDA world could be remarkable, and will certainly spawn discussion and speculation about future Apple involvement. No hints at official Apple involvement have surfaced... though even without Apple's involvement, the emergance of a relatively "open" platform may be very interesting.