I'm no management guru but I can see a couple of major problems:
(1) Some teams are necessary but won't make a direct profit, eg. internal IT, customer service.
(2) It could encourage a team to make a profit at the expense of another team; eg. the Office team might release a buggy product quickly (maximizing their profit by not testing it) knowing that the customer service team are the ones who'll suffer a loss supporting it.
Good points. Some creativity is in order when it comes to structuring the teams. For example the Office team could be responsible for customer support themselves! I'm only half joking. Think about the incentive that creates for making an intuitive and easy-to-use product.
(1) Some teams are necessary but won't make a direct profit, eg. internal IT, customer service.
(2) It could encourage a team to make a profit at the expense of another team; eg. the Office team might release a buggy product quickly (maximizing their profit by not testing it) knowing that the customer service team are the ones who'll suffer a loss supporting it.