Your minimum tax payable will of course take into account the personal exemption; that's where you start off. Whatever that amount is, is the trigger point at which you start paying taxes, unless you're a single parent, where you have equivalent to...or are a single earning spouse.
So it's not raising the threshold to $38,000; it's raising whatever that bottom taxable threshold is. Because of indexation of these brackets now, it automatically goes up year after year after year.