How many MBA programs to apply
That really depends on how desperate you are about getting your MBA at this point. If you definitely want to start your MBA in the year you're targeting then make sure to apply to 1 or 2 safety programs. Include as many realistic and stretch programs as you wish as long as you are passionate about the possibility of attending them (btw, always apply to at least 1 realistic and 1 stretch program - you don't want to miss out on any opportunities!). The typical applicant will apply to 4-6 MBA programs, in tough years (such as the class of 2011) maybe even to 5-7 MBA programs. Some will only apply to 2-3 stretch programs because otherwise it is not worth leaving their current job and the opportunities presented there. It just depends on your situation.
Keep in mind, however, that each additional MBA application will obviously require additional time. A rough ballpark figure would be 20-40 hours for the first application, depending on how easy it is for you to write essays. Each additional application will take much less time because you can copy/paste some parts of the essays. Try to limit the copy/pasting though (because the adcoms will tell how much effort you put into your application) but this will come natural as you do your research on each program and have different things to write about. Similarly, remember that each business school will also want to see that you demonstrated particular interest in their MBA program. This means additional time for campus visits, information sessions, research, etc. Lastly, don't forget your recommenders! Even though some of the recommender questions are similar, they will have to write a different recommendation for each business school. Recommenders then might also just start copy/pasting the more recommendations they have to write (which the adcoms will again notice).
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