Toronto's pretty middle-of-the-road. High provincial taxes compared to most states, but lower federal taxes.
This never occurred to me before, but Obama's tax plans are actually pretty good for the Raptors; in increasing top-earner taxes in the states, in gives Toronto a bit more of an edge and will likely edge them into one of the better tax markets for NBA players. The top earner tax bracket in the states is jumping from 35 to 39.6. By my count, that would raise the federal tax rate of every US NBA market to the point that only Dallas, Houston, Memphis, Miami, Orlando, and San Antonio will be lower, and even then only by a percentage or two.
edit: yeah, to what Puffer said, it's probably more complicated across borders. It would take someone who actually knows anything about taxes (my 2013 forms haven't been touched and April 29th now) to say how this actually applies.