Android 2.1 is pretty damn close. 2.2 seemed to be a little worse.
Main example: it used to be if you had someone's address in your contacts, you could hold down the search button until the voice search prompt came up, then say "Navigate to <person's name> and it would pull up Google Navigation on that person's address.
Around 2.2 Google seems to have removed the ability to search your contacts from Google Maps. I'm not sure if this is a bug or a decision that searching your own contacts won't generate ad revenue. In any case, what happens now is it gives you a popup of search results for that name in your vicinity and asks you to choose, usually there are like 20.
There should be more voice apps like GOOG 411, not less.