Great Indian City Name Tamasha

I remember couple of years back, when i was in my school used to follow the news channel especially the weather report and used to compare temperatures between the 4 metros, Delhi, Bombay, Calcutta, Madras.

Move to the present day and we see the same report with the metros being read as Delhi, Mumbai, Kolkatta, Chennai. And another city to have changed its name is Bengaluru (the new name for Bangalore), not sure when Delhi will join the band wagon. Not only the metros but many other cities are going through name changes.

So I was wondering what could be the driving force behind changing the names of cities and the following points came to my mind,

1) We still want to prove to the world that we are free and independent, by showing the door to the names given by our former colonial rulers.
2) The old names did not reflect the history, politic, culture and language of the place.
3) Is it one of the populist measures adopted by politicians as it is one of the easiest tasks for them.
4) This is what majority of the people wished and have been addressing the city all the while.
5) Difficult to pronounce.

Well i could not think of any further points (maybe if you do have some please feel free to comment about it).

I believe the government has better things that it can do to a city than just renaming it. Has renaming Madras to Chennai reduced the heat, has renaming Bombay to Mumbai resolved the water logging during rain there, has renaming Bangalore to Bengaluru resolved the Kaveri issue, well it has not.

I for one am neither against or for renaming a city, but i believe there are far more important and pressing measures which the government should implement more seriously.
But if anybody can let me know if there are any other reasons behind renaming of various cities, please do feel to drop your comments.

Sammy