I'd be curious to see how they handle the back end, especially as some others pointed out it does make calls that seemingly require some hook into the OS. As for its usefulness, I doubt it will really take off beyond being a decent prototype. It relies on image matching so if you use and change a custom icon set all your scripts would be kinda worthless. Same goes if the programs you are "screenshot scripting" receive a major overhaul in the GUI department. Until it can address those issues, I doubt it will really take off.

As a preface to my comment, IANAL. If you look at how states collect sales taxes from online sales, they can only "force" online companies that have a physical presence in their state to charge sales tax to residents of that state -- if the online business is outside the state, the most the state can do is require anyone who makes an online purchase to be a good citizen and report it to the revenue service and pay taxes on it. I think Massachusetts will run into the same situation, they will be able to enforce the laws on businesses that have a "presence" in Massachusetts but any business that does not have a presence will probably be exempt or could make a very strong legal case to be made exempt since they are not physically located in any way, shape, or form in Massachusetts.