Oh, the horror! Google hijacks 404 pages!
The reality is that the new Google beta toolbar doesn't hijack the 404 page if the site provides a 404 page or other form of web error handling. I tried the toolbar out this morning, and the only case I found where the Google toolbar provided a search page is the site matching the screenshots below, and the site given in the original post on this topic. The latter site provided a lame looking redirect back to the main page. However, other sites that redirected back to the home page for 404 errors did not have this problem, so the problem seems to be unique to this site.
If you've ever seen default 404 error handling, you know it's basically useless.
Compare that with a page managed by the toolbar.
I would expect a search engine toolbar to provide useful, alternative methods of finding the content if the web site uses default error handling. However, according to Codswallop, Google steals your visitors.
Why is this “helpful” behavior bad? As well as a link to the domain root they provide a prominent search box pre-filled with search terms. The temptation is going to be to hit that search button, effectively taking away your visitor.
I would say any webmaster that doesn't provide effective error handling pages for 404 errors doesn't really care about losing visitors, do they?
update Matt Cutts from Google explained that the toolbar looks for a result larger than 512 bytes. The example page is nothing more a broken HTML page, with a meta refresh and a link, all of which is less than 512 bytes. Those sites that do a direct redirect don't, of course, return 404 to trigger the toolbar. End of story.end update
What really surprised me about this story, though, is that if people are so quick to accuse Google of 'evil' behavior in an innocuous situations like this, why was the idea of Google helping to bail out Yahoo to keep the latter out of the hands of Microsoft seen as a "good" thing? I would think a search engine monopoly in the hands of Google would be potentially more evil than Google providing useful features for default 404 error handling.
This environment is confusingly inconsistent at times.
