In reply to SkyFonts: Beta:
Seems like it would be pretty easy to hack
This seems full of holes.
I doubt that.
I am not sure for which “side” you are arguing. For 20 years font users complain that they have to pay the full font license, before getting the chance to try the font in their design apps on their machines.
Skyfonts makes a lot of sense in this regard. Try the fonts free of charge, present different options to your clients. And it's also great for something like recreating a logo with 5 letters, which you have just got as JPG image from the client. Now you just pay for 1 day to use that font and you don't have to buy the full license.
I find that much more convincing than Fontslice – especially, since Monotype has almost all the fonts the users really want to use.