Porshyen, I'm not too clear about "...nor did you offer enough information here." but to answer some of your questions:
-Which program is the better fit?
I intend to visit both schools but I doubt that just visiting is enough as sometimes, first time feelings might not really be accurate. Also I feel professors and students may just appear 'nice' on that day just to attract students.
-Which professors have research interests closely related?
Prior to applying to both schools I researched the departments and found at least 3 different professors whose research I really like (in the area of Distributed Systems). I have read that "1/3 of incoming students change the fields specified in their SOP when they eventually enroll..." and I think I will change mine.
But now, I think I'm interested in Software Engineering and UIUC is pretty good at this with at least 3 professors research that I really dig. However, I have not made up my mind about exclusively pursuing Software Engineering because there are still other areas I really like: HCI, Distributed Systems, Networking. Consequently, I don't want to pick UIUC just because of Software Engineering because I am not 100% sure that's what I want to do. Moreover, I wrote about working in the area of Distributed Systems in my SOP for both schools because that's the area I worked on in my past research projects.
-Importance of location: I like a safe environment and I've read that both are relatively safe. I prefer a quite place and it seems both are not really like huge cities. Now, I don't like cold! But both are very cold so I've got no choice anyways. Urbana is cheaper in terms of cost of living but the stipend for Cornell makes up for the cost of living in Ithaca too. So everything seems to even out. Meanwhile, I like the idea of randomly driving from Ithaca to NYC to see Times Square
-Interactions with both schools: so far, both have been quite responsive. Some UIUC profs already emailed to say hi (I think that's pretty nice) and senior PhD students are already willing to answer my questions. Same for Cornell
-What I want to do after graduation
Work in industry research for a while, dabble in start-ups, return to academia as a prof (that's the only reason I'm doing this PhD anyways). Both schools seem pretty good in these areas. I recently found out about Cornell NYC tech and it seems that an entrepreneurial environment is pretty much growing bigger there.
TL;TR
--Cornell and UIUC have profs whose research I dig a lot
--They are both in the middle of nowhere so nothing huge abt locations
--I intend to visit both schools but I doubt that one time visit might help make a decision