AFAIK, Geo-Wand was described as an application "using on-board accelerometers and compass". The N900 doesn't have a compass, so an application couldn't detect which direction your pointing at.

OTOH, it would be nice to have a simpler version: Just a map that shows your surroundings and has clickable symbols on it for each item found on Wikipedia.

You could mail Pierre-Luc Beaudoin, the author of Map Buddy, about it. His application does exactly that, only it displays local businesses. Piere-Luc could re-use the existing code and only change the database he sends his queries to.