The SimpleGeo post talks about finding coffee shops near a user's coordinates (reverse geocoding)... isn't this what the Google Places API does? Or would the AUP of the Places API limit developers where SimpleGeo would not?
Google Places gives all business for a given location and radius (you can then grab expanded listings of whatever's found), but not specific businesses like coffee shops, however this kind of functionality will probably come soon, and for server side lookups.
Google Places API: http://code.google.com/apis/maps/documentation/places/