A good way to find research groups in your area of interest is to read papers\journals in you area in see where the authors are from.
For example:
http://academic.research.microsoft.com/?SearchDomain=2&SubDomain=18&entitytype=2
I didn't hear of that program, but CMU, Cornell, and Wisconisn-Madison are awesome.
Have you considered visiting other campuses? you might be positively surprised.
One good way is to ask professors at your undergraduate institute for their opinion.
Browsing over universities in this ranking is not a bad idea as well:
http://grad-schools.usnews.rankingsandreviews.com/best-graduate-schools/top-science-schools/computer-science-rankings
From my experience, if you wait a bit longer you don't risk your acceptance at all. Your place is guaranteed. But the program might offer you a bit more money (in terms of a one-time stipend) as a incentive for you to enrol.
Have you visited Ithacha? It might be that you like or not like to location. It really depends on your interests, hobbies and where you aspire to live.
Congrats dude! Happy for you.
Just to be sure -- Don't accept their offer right away. Wait to hear from other universities and also about the financial information.
If there is a visit day, I strongly recommend you attend it before you make your decision.