Basically, this is an acknowledgment that the program as currently was ill conceived (see here and here).

They will be accellerating the small airborn and ground vehicles, and soft pedaling the armored vehicles:

The moves will shift the focus of the overall FCS effort to infantry brigades instead of armored units. The Army will also work to get large numbers of robots and miniature aerial drones — both of which are designed for use in crowded urban areas — out to forces in Iraq and Afghanistan by late 2010, instead of in 2015 or 2016 as initially planned.

This is an admission that it will be infantry, and not armored units that will be necessary in the most likely future war fighting scenarios.

The manned ground vehicles will be small and lighter, and so in a number of ways inferior to their predecessors, so this should come as no surprise.