Schools want to see what you have done in the past. Have you progressed? or are you at the same job since graduation. Promotions matter a lot and add a lot to your profile. Many schools like UNC schedule interviews even before you submit your essays. They just ask for your resume and interview you. Other schools will give the interview-er your resume and a list of questions. So you can see that your resume is one of the most important pieces of the b-school application.
It is also important to choose the right resume format. Most top schools have a similar format, which really looks plain and simple. I personally dont like it that much, but thats what schools prefer and like to see. Just google mba resumes and you see many examples. Remember it should be very simple.
Make sure there are no spelling mistakes, the best way to do this is to have a friend who has not seen your resume before review it. I often missed small errors cuz I had looked at my resume way too many times.
I have been getting a lot of requests to review stuff, so in a day or two I will post another post with details on how to send me your stuff.
As always, questions and comments are welcome.
Anshul