Networks In Motion, Inc. has come out with Gokivo + Yahoo Local Search for only $.99. The catch is that there is an in-app subscription of $9.99 a month. It also requires iPhone OS 3.0.
Personally, I'm waiting to see what the price will be for the Tom Tom For iPhone. As long as there is no monthly subscription, I'll probably get it. I'd rather pay a $40 one-time fee than a $9.99 a month fee.