Since this is just recently becoming noticeable in the oceans first signs of effects on the wildlife are beginning to appear. The most noticed problem is inability to form calcium carbonate structures, which has been effecting mostly corals and animal that secrete shells.
In one study done at Oregon State University there was signs that acid environment during larval development of oysters lead to an inability to grow correctly and to low recruitment levels This immediately has an affect on businesses using oysters and other shelled animals to make a profit, but will soon be noticeable in the environment. The reduction of these animals may be an indication of future problems to come and act as a sort of "canary in the coal mine" for the ocean.
Although the results of this ocean acidification have not been immediately evident there are beginning to be signs that it is affecting the wildlife. Since there are calcium carbonate animals such as corals that are already being greatly reduced in numbers it is important the situation becomes controlled as soon as possible. Also, since areas of upwelling will soon be bringing waters that were previously acidified the situation will not just get better on its own.