In conjunction with the redesigned BMW 7-series coming in 2009 or 2010, ZF will introduce a new eight-speed unit of their own. Whether or not adding more gears will actually improve the efficiency is irrelevant in the upper strata of automobiles. With cars like this, mine simply must be bigger than yours. It seems that when going past six or seven gears, the added weight and complexity will outdo any potential efficiency gains. The alternative approach of optimizing the performance of a six-speed seems like it would make more sense.
[Source: Automotive News - Subscription required]