It's not that simple. 183 days rule is to decide your status as resident or non-resident of Canada. There are many other rules you need to look at to determin if you need to file tax. For example, if you have to pay tax for 2007, if you sell taxable Canadian property in 2007, if you have to contribute CPP, etc. Get a tax guide for non-resident from CRA helps a lot if you want to handle this by yourself.
I have a question need your help too. If I reside in Windsor and work in Detroit like you did before, do I need a TN visa? What are pros and cons as opposed to live in Detroit? -xjurum(要塞玫瑰) 2008-4-6