According to the LLM/BCL post, if there is only one applied field (which, I presume there is for your course as you are looking at the Jan 23rd deadline) then the most popular colleges are probably worth avoiding as they may well be full. One post explains how they were told that the application never went to their first choice college for this reason.
I think a lot of people don't put a great deal of thought into filling that part in because A) they don't really expect to get their first choice or B) they just want to get in.
Really, if you haven't been taken by any yet, I'd just put anything in and get the application sent in. Stick a couple of the more 'famous'colleges in if that is what important to you but generally, like undergrad, people don't necessarily go to the college of choice.