Discuss as:

Most popular cities in the world to visit in 2012

George Rose / Getty Images

A view looking down The Mall toward Buckingham Palace and Victoria Memorial in London.

In choosing a vacation spot this year, will you follow your heart or follow the crowd?

To come up with its second annual list of the 20 most visited cities in the world, MasterCard followed the money. The company's Global Destination Cities Index for 2012 ranks Istanbul as the fastest growing destination, putting it No. 5 on the list after London, Paris, Bangkok and Singapore.

Slideshow: See the most visited cities in 2012

“Despite sluggish economic growth around the world, the number of people traveling abroad continues to increase,” the report states. London leads the world in the two key criteria MasterCard considered: as both the most popular destination city for overseas travelers (they’re expecting 16.9 million foreign visitors this year), and in the average amount each visitor spends (their total spending there is projected to be $21.1 billion). Whether drawn by business or as tourists, London’s visitors from New York are the ones that travel the furthest and spend the most.

New York still ranks second by visitor spending (after London), which may explain all the foreign languages one hears while shopping at the Gap.

In the Asia/Pacific region, Bangkok leads in the total number of visitors and visitor spending and is expected to displace Paris as the third-ranking city by visitor spending. Dubai retains its rank as No. 1 of the top 10 destination cities in the Middle East and Africa.

Glitz trumps history in the People’s Republic of China, with Shanghai ahead of Beijing by five ranks. And though to many minds Barcelona outcharms Madrid, Spain’s capital remains the more popular destination.

Although Rome hasn’t lost any of its charm, it has slipped in popularity as a tourist destination, falling below Seoul, Kuala Lumpur, Frankfurt and Dubai. Perhaps economic forces are at play.

Still undecided about your next destination? Check out the slideshow to help decide.

Deborah L. Jacobs, a lawyer and journalist, is the author of Estate Planning Smarts: A Practical, User-Friendly, Action-Oriented Guide. You can follow her on Twitter.

More from Forbes.com