get rid of it !!! yahoo is a register trade mark !!! even if you make money from it yahoo is going to ask you to pay them even more !!!
Yahoo is a Trademark! Once you go live with that domain they will sue you and you will have to pay ...a lot. Nobody is allowed to use Trademarks, that's the reason a name is registered as trademark. If you don't know what a trademark is ...go google it and after you might consider an online venture... Good luck!
In your registar control panel find a option to drop it or delete it. Procedure may vary depending on registar.
Actually...isn't Yahoo technically a generic enough term to use? Yahoo is like an expression, like Ouch! or Eew!
I would say using the domain in this context would constitute infringement regardless of an exclamation point. Either way they can hire more expensive lawyers for sure.