Globalization says wikipedia is the process of international integration arising from the interchange of world views, products, ideas, and other aspects of culture. In particular, advances in transportation and telecommunications infrastructure, including the rise of the Internet, are major factors in globalization and precipitate further interdependence of economic and cultural activities. (http://en.wikipedia.org/wiki/Globalization)
It has helped in reducing differences and has made the talk if not the idea of 'one world' possible. It has helped in the growth and movement of liberal ideas like democracy, freedom and has helped in improving the standard of life better.
It is strange to observe the fact that the more globalized we become more similar we get in terms of the way our cities look today- the same big multi national brand of clothing, shoes, food chains, highways/ motorways, etc. The same chains are present everywhere selling almost the same products (with a little tweak here and there to suit local preferences).
The idea of development promoted by globalization is very west-centric and first world oriented. The third world in its efforts to play catch up has had to deal with problems and issues of displacement of its local population for land use by big corporates, pollution (air/ water/ noise/land), slums etc. The rise of urban cities in the third world has not been without these and many more problems for every developing nation. The new cities have pockets of development- swanky malls, flyovers, housing societies with modern amenities, tall modern office buildings and complexes surrounded by slums and urban villages. A very good example of which is Gurgaon, with big beautiful modern buildings and problems of infrastructure like roads, water, electricity etc. The growing population has not helped at all. The trend of developing cities to ape western models of cities without any consideration of local conditions has created more problems than solved for the administration and the citizens of those cities.
The big metro cities want to be like New York, Shanghai, etc. but if all cities are going to look like same, and serve similar world food, with same products, the world will surely become a boring place.
Globalization has also meant a certain minimum standard followed in terms of quality of products. A relative of mine visiting from Europe was very happy to see Mark and Spencer stores, Subway chains etc. (unlike six years back in Delhi when she visited last time) , but for shopping for clothes she still preferred Chandni Chowk for its variety and prices.
Technological revolution fueled by globalization also means that governments of various countries have to be careful not just about their local population but also world opinion which is just a tweet away. The democratic movements in Arab world are a result of people being aware of their rights and fighting for themselves. Pictures of Japanese Tsunami united the whole world in feeling the Japanese pain in the same way, it is condemning Syrian government for its excesses against its population.
There is still debate on whether the inequalities (between the developed and under-developed world, between rich and poor) have grown or lessened thanks to globalization. Like everything else the answer lies somewhere in between, with both good and bad sides to it.