How dow you know when the Mortgage Insurance Premium reported in box 4 of the 1098 Mortgage Interest Statement is deductible? And on what form.

If the mortgage insurance contract was issued in 2007 or later, it's deductible as long as it's in conjunction with home acqiusition debt that is secured by your home. You can read more details here:
Publication 936 (2009), Home Mortgage Interest Deduction (http://www.irs.gov/publications/p936/ar02.html#en_US_publink1000229966)