Its breaking news right now. Ovi Maps will provide free navigation. Its available for download on the N97 Mini right now. But it wont be working on the original N97 (as of now) since a minimum of 20mb is required in the C drive for the ovi maps installer to start working. Original N97’s support will be added in a weeks time. V2.1 firmware release also scheduled for next week ..
Update 1: N97 support from 28th Jan. Thanks @chansearrington
Update 2: You can install Ovi Maps on N97 right now. Not officially supported though.

Some of the features of the new Ovi Maps:
My Position: One click pinpoints your position on the maps. Now with network and A-GPS for precise navigation.
Find Places: Quickly find the places you need nearby, and cities, streets and addresses worldwide, with the new one-box search.
Drive: Free turn-by-turn navigation, with voice and visual guidance in over 70 countries. Includes real time traffic information, lane assistance, speed limit warnings, and automatic rerouting to help you arrive safely and on time.
» More: Free navigation with Ovi Maps on N97 Mini