Namma Metro opened its first stretch on 20 October 2011 and now runs several colour-coded lines, with more under construction. Kempegowda International Airport at Devanahalli replaced the old HAL airport in 2008.
Civic governance has been reorganised several times, from the Bangalore City Corporation to the Bruhat Bengaluru Mahanagara Palike (BBMP, 2007) and, more recently, the Greater Bengaluru Authority, which oversees several new city corporations. For how to use the metro today see Getting around by metro.
Further reading: Namma Metro on Wikipedia.