Ali Ayub Khan also listed as one of his addresses the same Chicago apartment house as Sabash Gurung is staying in with his brother. Gurung is the Nepalese who was arrested at O'Hare Airport with a large stash of weapons (knives, a stun gun, etc.). The FBI said (or implied) that the Ali Khan who lives in the same apartment house as Gurung is a different Ali Khan, that it's a coincidence of names. But this seems not to be the case -- in fact, there is a newspaper article on Khan, dated well before Gurung was in the news, which gives that Chicago address for him. See this thread for details.
Some of these apartments seem to be rented just for the purpose of having a meeting place for a cell in a particular city. Or maybe some of these people move around quite a bit. (After all, the cells have to communicate with one another, if only indirectly, so there are probably some individuals who are members of 2 or perhaps even 3 cells, slthough most people will be members of only one cell and will know nothing about anybody else.