Steve Citron-Pousty recently wrote about whether Google made the data change too soon. He talked about how his wife has always used Google Maps, but it has got her lost four times in the past week and she has now switched to using MapQuest or Bing. And Google got Steve lost in the Bay Area last week too. Maitri says she is "splitting up with Google Maps" over issues in Ohio, as "there is no excuse for such shoddy mapping when MapQuest and Yahoo do exceptional work in this area the first time around". She links to an article in a Canton, Ohio, newspaper about how the town was mis-named after the recent data change (we call it Canton, Google calls it Colesville). James Fee pointed out an error with Google showing a lake that hadn't been there for 25 years or so. Matt Ball did a round-up discussion on the importance of trusted data. The well known tech journalist Walt Mossberg reviews the new Motorola Droid phone (which uses the new Google data for navigation), and in passing says when reviewing the navigation application "but it also gave me a couple of bad directions, such as sending me the wrong way at a fork in the road". And then in news which is presumably unrelated technically (being the in the UK), there was a lot of coverage of a story about how Google Maps contained a completely fictitious town called Argleton - which even though a separate issue does not help the public perception of the reliability of Google Maps data.
Update: see quite a few more stories about data issues in the comments below.
So anyway, this is a long and maybe somewhat boring list, but I think that it is worth getting a feel for the number of stories that are appearing about map data errors. As anyone in the geo world knows, all maps have errors, and it's hard to do a really rigorous analysis on Google's current dataset versus others. But I think there is strong evidence that the new Google dataset in the US is a significant step down in quality from what they had before, and from what Microsoft, Yahoo and MapQuest have (via Tele Atlas or NAVTEQ).
Google clearly hopes to clean up the data fairly quickly by having users notify them of errors. But looking at the situation, I think that they may have a few challenges with this. One is just that the number of errors seems to be pretty large. But more importantly, I think the question for Google is whether consumers will be motivated to help them fix up the data, when there are plenty of good free alternatives available. If Google gives you the wrong answer once maybe you let it slide, and perhaps you notice the link to inform them of the problem and maybe fill it out. But if it happens a couple of times, is the average consumer likely to keep informing Google of errors, or just say "*&#% this, I'm switching to MapQuest/Bing/Yahoo"?
Google has made some reasonable progress with Google MapMaker (its crowdsourced system for letting people create their own map data) in certain parts of the world, but these are generally places where there are not good alternative maps already, or people may be unaware of alternatives like OpenStreetMap. So in those cases, people have a clearer motivation to contribute their time to making updates. People who contribute time to OpenStreetMap have a range of motivations, but in general for most of them it is important that the data is open and freely available, which is not the case with Google (at least not so much, I won't get into the details of that discussion here). Most if not all the people I know who contribute effort to OpenStreetMap (myself included) would not be inclined to contribute significant updates to Google (except for some experiments to see how good or bad the update process is).
Consumer confidence is a fickle thing, and you probably don't need too many stories in the newspapers of mishaps due to bad data, or more than a couple of direct experiences of getting lost yourself due to bad data, to switch to a different provider (especially when you are choosing between different free systems - you have a bit more incentive to stick with a navigation system and try to make it work if you've spent a few hundred dollars on it).
The risks are even higher with real time turn by turn directions - no matter how many caveats you put on it, you are likely to get some drivers who follow the directions from the system and don't notice relevant road signs. You only need a couple of accidents because people drove the wrong way up one way streets because of bad data to damage consumer confidence even further.
So I think it will be very interesting over the next few months to see whether the data quality issues are bad enough to result in significant numbers of users moving away from Google Maps in the US or not - and whether Google will get significant uptake in terms of number of people contributing error reports in the US (beyond the initial wave of curiosity-driven updates just to test if the process works). Obviously the answer to the second question is likely to have a big influence on the first. Stay tuned ...