There are more established players in the game, for whom it would be trivial to add this feature. Xmarks ended(?) their business with millions of users once Ch

There are more established players in the game, for whom it would be trivial to add this feature. Xmarks ended(?) their business with millions of users once Chrome and Firefox decided to add distributed bookmarking. It's a cool idea, but I'd be cautious about building a business based on it.