maps.google.com works great though. I wish I wasn't supporting Google's massive operations but it is convenient to use.
AFAIK they don't have path/street data, just a massive location dataset, so you can't use it for directions by itself.
OpenStreetMap is a great datasource and set of APIs though, on which other people have built really useful map applications. But OSM itself is not an attempt to compete with all of Google Maps, just to provide high quality tiles, path/nodes and place database to developers.
Also the address search is good but not perfect due to lack of data but also limited software.
But the nice thing about OSM as a developer is: you can do anything with this data. Build your own address searcher, routing engine and mapping stuff etc.
So if you find something missing, you may consider spending the time to add the missing information so that we can have maps that are owned in common: https://en.wikipedia.org/wiki/Open_Database_License