Maemo 5 should be able to handle vector maps. As to commercial alternatives that use vector maps they exist but may not yet to be ported to the Maemo 5 environment. Maemo Mapper on the N810 meets my needs so I've not researched alternatives. There are multiple GPS applications that have been used on the N8x0 which are covered in the forums. That might be a place to start looking. OVI might be another place to look.