We got an email from Mike, who said he just got his first acceptance letter and is waiting to receive the I-20 form. But:
"...there are still 2 other universities i'm interested in. IS IT POSSIBLE TO HAVE TWO I-20s FROM DIFFERENT COLLEGES AT THE SAME TIME THEN CHOOSE ONE AFTER RECEIVING THE I-20s?"

The answer is, yes. It is not only possible, but normal. You will get an I-20 from each school that accepts you. You just have to pick one before you apply for your visa, and then use that I-20 during the visa process.

Here's what the Department of Homeland Security says:
Each school that accepts you will mail you a Form I-20.  Before you apply to pay the I-901 student fee, you must select one school and use that Form I-20 to pay the I-901 fee and to apply for the correct student visa.

(And the same information from the ICE's SEVIS site)

Hope that helps, and congratulations to anyone lucky enough to get multiple I-20s!