I know Mavic says that. I've been doing cyclocross racing on them with 35mm tires. I guess if you plan to use wide tires, though, the A719 is a better choice.

As for curb hopping and such, the wheel build is more critical than the choice of rim. Most rims on the market can handle a lot of curb riding if they're well built (assuming a reasonable spoke count relative to bike+rider+cargo weight). OTOH, even the best of rims will suffer if the wheel isn't well built.