It all depends on your preference as to which State you find most desirable, however, from a tax point of view, it would be preferable to be a resident of a state that has a lower individual income tax rate.
So, it is worth examining the individual tax rates for both States and the State that has the lowest tax rates would be financially more desirable to you.
For the Tax Year 2008, Iowa State has 9 tax rate brackets, with a rate of 0.36% at the lowest end and 8.98% at the highest rate.
For the Tax Year 2008, Wisconsin State has 4 tax rate brackets, with a rate of 4.6% at the lowest end and 6.75% at the highest rate.
Assuming your effective taxable income puts in the highest tax bracket, than clearly Wisconsin appears to have the lower tax rate and so from the tax point of you, it would be more preferable to rent in Wisconsin State as its highest tax rate offers a tax rate that is at least a 2.3% (8.98% - 6.75%) lower than Iowa State.
Assuming your effective taxable income puts in the lowest tax bracket, than clearly Iowa appears to have the lowest tax rate and so from the tax point of you, it would be more preferable to rent in Iowa State as its lowest tax rate offers a tax rate that is at least a 4.24% (4.6% - .36%) lower than Iowa State.
Thus, I would recommend your Tax Adviser to help you determine what your tax bracket would be in both states given your 2009 projected taxable income based on your husbands new job. Generally speaking, the State with the lowest tax rate would be choice to rent as this would be your principal residence.
But, there are several other factors that also come into play as your husbands income would be taxed in Iowa as a Non-Resident Income, assuming you maintain a residence in Wisconsin. In this case you would get taxed at the Iowa tax rate but you would get a tax credit or deduction for taxes paid in Iowa so that you can offset the tax liability from Iowa State on your Wisconsin.
Thus, you may not gain a significant tax benefit at the end of the day or it may be a very marginal tax benefit at the best. Thus, it might be prudent to simply find a suitable rental in Iowa State to avoid the tax hassle of filing a Multi-State tax returns, which may clearly cost you more in tax fees!