I was told the 5-series will also get the new I6 engine (same as the one in the new 3-series) and they would be coming sometime this May as 2006 models. This guy is the salesman from whom I have bought my last 4 BMW's and he advised me against buying or leasing the 525i or 530i until May when the new engine arrives. He also stated that there would be no engine change on the X3 or X5 (make sense).