The 2009 deadline for Board of Review appeals is August 10 for all townships in the County, with the exceptions of Groveland which is August 31, and Morton which is yet to be determined.
In other words, if you feel your property is assessed at more than it is worth, you have only until August 10, 2009 to do something about it.
Contact your Realtor for assistance in gathering comparable sales data that will support your argument for a lower fair market value.
The appeal forms can be downloaded here.
It is the homeowners responsibility to keep your property assessment fair and reasonable.