Ruth and Perry are absolutely correct. Remember that you agreement is with the landlord and you must abide by the terms of that agreement. What happens between your landlord and his/her bank is immaterial to you.
Also, do not assume that he is not paying the bank. Even though it is in pre-foreclosure, he may be putting money aside to bring down the default amount.
In addition, you should be planning accordingly so that you are not left out in the cold. Rentals are very high right now and extremely difficult to get into. If you have a lease, you must abide by the terms of the lease, however, there are some exceptions to this, but you should speak to an attorney about your particular circumstance. There is also a rental advocacy in Milwaukee County that gives free advice regarding your circumstances. I do not know off the top of my head, but if you don't find it on the internet, let me know and I will find it for you.
Best of luck to you.