The monthly mortgage insurance is 100% tax deductible, assuming your combined household income is $100,000 or less, annually. Your ability to deduct this is reduced if you make $101,000 and completely phases out after $109,000 in annual earning. And yes, right now, that will likely not be tax eductible after 2010. For FHA loans, there is no lender-paid monthly mortgage insurance. But if there were, you would likely be paying 6% interest for your loan vs. 5% interest.
However, the key here is to remember the benefits that FHA loans bring. One of the mail benefits is that you only have to put 3.5% down. Isn't paying mortgage insurance, whether it is tax deductible or not, worth the trade off of only needing to put 3.5% down? Think about it this way. If you paid $400,000 for a home, without FHA loans, you would need to put 20% down, or $80,000. With FHA, you put 3.5% down, or $14,000, and you would be paying about $177 a month in mortgage insurance. I would take that deal all day long to avoid having to give the lender another $66,000 to buy the house.
FHA loans are fantastic loans and although the mortgage insurance makes them seem expensive, they allow you hold on to your hard earned cash. Good luck with your purchase!