If you're too impatient to wait for Google to release its own iPhone app or Safari-optimized version of Google Analytics you might want to check out myAnalytics. This $1.99 iPhone application (app store link) lets you see a general overview of how your sites are doing, and stores the data locally on your device so you can access it when you're away from a data connection. Considering Google's most recent release of Analytics requires Adobe Flash, this is the easiest way to get it short of getting your hands on a real computer.
While convenient, it is worth noting that myAnalytics can get bogged down if you intend on using it for more than eight different sites. Also, the current version only shows you basic numbers and a small chart, unlike Google Analytics, which lets you dig deeper into each component of your site. Version 1.1, which is coming soon, will let you view each individual stat on its own graph, which is a good start.
Related: Sergej Müller's mobile Safari-friendly version of Google Analytics (Note: this only lets you see page views and visitor counts.)