Global guerrillas set off seven bombs in quick intervals over a 20 minute period during rush hour on Mumbai's (a city of 16 million and India's commercial hub) commuter rail system. At least 163 people died and a thousand were wounded mostly in first class cabins, on a rail system used by 6.5 million people a day. Cascading systems effects included jammed phone systems and an indefinite suspension of all commuter train service (which will in turn cause jammed highways and reduced business activity).
The radical improvement in technique, targeting, and coordination demonstrated in Mumbai is yet another example of how the innovation generated by open-source warfare is now global. Hacks on warfare's source code generated in Madrid, London, and Thailand have now made their way to India.
As anticipated, this attack is also a sign that future attacks will increasingly target systems rather than low yield targets of symbolic terrorism. As methods of system disruption improve, attacks will be aimed at more precise systempunkts that underly modern economic activity, particularly in highly populated urban zones. One key vector of activity will be to use repetitive attacks to push urban centers to lower economic equilibria (see Urban Takedowns for more) -- it is potentially possible, once the data is developed, to calculate how many attacks are needed to achieve the seven percent "terrorism tax" that will accomplish this descent. Another vector will be aimed at improving the effectiveness of cross system cascades of failure to maximize total levels of disruption (these early demonstrations are fairly crude in this regard).
Update: There's perhaps a little confusion on this analysis. I point to the Mumbai attacks as an example of a trend line on the evolution of warfare not as a singular event that will rock India to its core (far from it). Also, to Thomas Barnett's critique of 4GW and systems disruption: I believe that global guerrillas will not collapse the West any more than the Internet collapsed Microsoft's monopoly. Their emergence will, however, change things. Don't think Vietnam. Think Israel.