A monopoly should be defined by barriers to entry, not just market share. There's nothing preventing other large companies from entering the search space, and in fact many of them have (yahoo, microsoft, etc).
There are true monopolistic firms like Comcast or Time Warner, where there are serious logistic/economic barriers preventing other firms from entering the market. This doesn't seem like one of them to me.
There are true monopolistic firms like Comcast or Time Warner, where there are serious logistic/economic barriers preventing other firms from entering the market. This doesn't seem like one of them to me.