This is the 2nd report I've seen of this on iOS today. viewtopic.php?f=3&t=23767 was posted before you did. (And this is a client-side issue and has nothing to do with the map, so I think getting more folks into that thread in a similar situation would be sensible.)
FYI, you can tap-hold on the map to add a favorite or navigate as well. But you'd have to pan the map to find it first in this situation until we can figure it out.
I'm in Menlo Park and I just installed the app on my iPhone. When I go to the navigate screen I started by trying to enter my home address in the Home field. From what I understand a list of addresses should pop up when I enter my address but nothing happens at all. When I press search the keyboard disappears and it just displays my text without jumping to a selection screen. It turns out I can't enter any data for Work, Favorites or anything else.