First and foremost, this has been around before gas prices went sky high, so in that regards the Snopes article itself is wrong. Additionally, it just says acetone will eat up things. Well this is true, but it failed to mention the treat levels used in gasoline. Generally speaking, the treat levels are around 3oz / 10 gallons of gas. So the concentrations are hardly harmful. So that just goes to show you snopes is not the end all be all in final words.
That all said, I have tried this before, including in the Grand Prix and have never noticed any thing that was significant that would warrant the need to keep acetone around for anything other than as a solvent.
Furthermore, the only real ways to assist in the vaporization of fuel is to warm it up, which of course, if not done properly can cause other issues. You can atomize it more, but that takes better injectors and higher fuel pressure and Ive never seen any real experiments on this.
This is why you get better mileage in the summer than you do in the winter. The air is hotter, so the fuel is warmer and there is less oxygen per pound of air (density).