What you want to do seems like it is OK, as long as when you are showing routes you do not display the user position. I am basing this on the docs here (linked to from the MKMapView documentation):
http://code.google.com/apis/maps/iphone/terms.html.
that state you cannot:
10.9 use the Service or Content with any products, systems, or applications for or in connection with:
(a) real time navigation or route guidance, including but not limited to turn-by-turn route guidance that is synchronized to the position of a user's sensor-enabled device;
(b) any systems or functions for automatic or autonomous control of vehicle behavior; or
(c) dispatch, fleet management, business asset tracking, or similar enterprise applications (the Google Maps API can be used to track assets (such as cars, buses or other vehicles) as long as the tracking application is made available to the public without charge. For example, you may offer a free, public Maps API Implementation that displays real-time public transit or other transportation status information.
Even that language I feel is a bit fuzzy on if you can show user location or not along with routes, if you do not adjust the map coordinates automatically to follow the user.