My personal choice for iPhone navigation apps is Navigon, and the Navigon 2.0 for iPhone offers new name, download options today. I'm downloading in now to give it a look.
If you're already a Navigon GPS app owner you'll find a significant free update at the app store today. If you haven't chosen a GPS navigation solution yet, Navigon has given you good reason to check the product out.
Short story is new UI, maps that you can select (instead of getting all of north america for example, you can only select the areas you actually need (drastically reducing the disk space required) and the prices are all dropped as well (North America $39, Canada or US only is down to $29).