The acquisition of JBOSS in Atlanta is important for a number of reasons. First of all, it demonstrates that you CAN build a platform company outside of SV or Boston. Second, it was a huge return for investors; on only $10M the exit looks to be $350M upfront in stock/cash with an additional minimum $70M earnout, or $420M+, all in about 5 years. Third, it demonstrates that you can build companies by flying in tier one venture; no local Atlanta VC's invested, the money was all Matrix and Accel.
Open Source platforms equalize the playing field where you can recruit talent; hence the ability of companies such as RedHat, JBOSS, as well as Solarmetric(started by MIT fraternity brothers of mine, and acquired by BEA) to scale up in locations such as Durham, Atlanta, and Austin respectively. I believe that with the shift towards Open Source, LAMP, AJAX, and other new platform technologies, other technology regions can compete with SV and Boston at a lower cost, faster time to liquidity, and less competition for talent.
I'm reminded of Dr. Analee Saxenian's book, "Regional Advantage". In that work, Dr. Saxenian explains why SV started behind Boston in certain key technologies, yet ultimately valley companies prevailed. Rt. 128 supplied Apollo, Wang, DEC...all gone, whereas the valley had SGI, Sun, HP, etc. The regional advantage of SV was due to an open culture of innovation, and collaboration even between competitive companies. Rt. 128 kept a model of tightly held, vertically integrated, closed cultures.
Open Source and Web 2.0 technologies represent another potential iteration of the thesis behind "Regional Advantage"...ANY region/network which encourages collaboration and ongoing co-opetition gets to play in this game.