While not getting a admit was a problem till now, multiple admits are no less a problem either. Because now finally the ball is in your court again. You need to decide which one to choose.
Different phases of application process require different skills. The skill required here is your socializing and networking capabilities. I don't have much to write here except than to stress that you need to talk to as many people as you can to help you decide.

The best people to guide you are students who are already enrolled in that particular program there. So, the algorithm should be as follows:

• Go the the University website and navigate to that program's website from which you've got a admit.

• Find someplace where you'll have a list of the class of students already admitted to that program.

• If you find their email ids right there then well and good. If you find only names of the students, go and look up the name in the directory of the University to get their email id. Almost all Universities maintain some kind of a online repository (a online directory) that will find students based on their name, program etc.

• Once you have got a list of some students from each University, send them emails.

You may not get responses from them. Don't worry, just keep sending mails to different students from the list you have. Remember the students who are already there are the BEST resources to tell you good and bad things about their Program/University. You need to poll a couple of them before you decide on a University.

Several Do's and Dont's for your email asking for advice:

• Don't write long emails to students. Graduate students seldom have a lot of time to read and respond to your long emails. Be very precise. Write that you have got these options enumerating the University/Program for each of your admits. Ask specific questions about the University.

• Ask what according to the student would be the best choice to make given your admits.

• Briefly ask all the finance/TA/RA, campus job questions.

• Make sure you don't write long paragraphs. Ask couple of questions in a tabular manner.

I write these 'obvious' facts because we often ignore that the other person may not have all the time on earth to answer your peculiar questions and may discard your email if it is not coherent enough. Be brief and precise.

You can checkout the University group/community on facebook/orkut and try to find if there is one dedicated to your specific program. You'll get a lots of contacts in any such group/community.

Your decision to choose a University must solely depend on the faculty and the courses that you'll take there. It should also depend on the financial aspects if it is a concern for you. Further, you should also take into consideration the weather of the place where your University is. You should not choose Universities in places of extreme cold if you are allergic to cold weather.

Once you have decided your University, send them a letter of acceptance stating that you accept the offer. It is also important that you intimate other Universities that you won't be joining them. This really helps them to manage their wait list better and issue offers to waitlisted students.