As a delhiite (atleast in the positive sense) who has moved to mumbai the following are the pro's and cons of life in mumbai...
Lets start with the pros
1. The city never sleeps - heartening to see people of all walks of life, age and sex hanging around till late at night
2. People dont fight as often. Road rash is less
3. Decent Public transport system - though the trains suck at peak time
4. Good historical places to visit and architecture of the fort area is fascinating
1. Pathetic roads - bridges are perpetually in the state of construction
2. Property prices - sky rocketing. The brokers are one breed to avoid, they make you feel worse than a beggar
Apart from these haven't spent enough time to compare but yes i definitely miss my friends in delhi :(.