Well, this "discount" doesn't lower the actual price, but it does lower the interest rate, which is part of the total that you pay.
You just really have to crunch the numbers to see if you are better off. Generally if you are not staying in the house very long, this will not make as much sense.
Points are indeed tax-deductible on a home purchase, but be aware that if you are doing a refinance, they must be amortized over the life of the loan. In that case they may not all be deducted at once.