[DirtyAndy]

Another issue with alternative ways of handling registration (and this is all a bit moot now, because I don't think anyone is ever going to change the laws and take all the parked domains back - except Libya) is how you would ever define that it is in use. People complain that they can't buy good domains when they have an idea for a project, but lets imagine you can buy any unused domain for $10 for your project. At what point do we determine that your project is never going to be viable and the domain should be surrendered? There are always discussions on HN about failed side projects, how would you feel if after 3 months, 6 months etc ICANN turned around and said you are not using that domain sufficiently, we're taking it back. I've got 5-6 projects that I have started that will probably never go anywhere, but I wouldn't want to give up the domain just in case.

Could you also imagine the costs involved with any arbitration process to handle that. If you had to build it into the average domain cost, you wouldn't be paying $10 anymore, in fact you might find a lot of domains are cheaper through the free market system that exists now.

[ohashi]

Defining 'in-use' is the biggest problem people stumble on when making that argument. I think you've hit the nail on the head with raising the sorts of issues that it would cause.

[Hexstream]

For one thing, having a crappy useless domain with ads should count as less "usage" than having just a page indicating that some project is being developed, without ads.