Oh wait...
Ok, serious mode. For years people have been complaining that Mozilla is too dependent on funding from Google. This is a way for Mozilla to fund itself without depending on Google. But that's not good either?
Maybe Mozilla should start nagging people for donations, Wikipedia-style? But that's not good either: lots of people complain about Wikipedia's yearly "begging" and say they would prefer to see ads instead.
What would you have them do?