The Wall Street Journal reports that the Google Maps app for iOS is almost ready for launch. "Google has been putting the finishing touches on the app before submitting it for approval to the Apple iTunes store, though it's unclear exactly when that will happen."
The new app will include all the feature from Apple's old maps app, but also turn-by-turn navigation. It's likely that Google wants to build a better app than the built-in iOS 6 maps app, so it must include turn-by-turn directions and flyover maps.
Even if Google submits the app for approval in the coming weeks, it's not obvious that you'll be able download it so soon because Apple could reject the app or delay its approval. The new version of the Google Search app for iOS was announced 3 months ago, but it was approved two weeks ago.
For now, you can use the Google Maps web app, which has recently added support for Street View. There's also the great Nokia Maps web app.