Google Auto-correcting Queries

I tend to make spelling mistakes when I type a search query, so Google's "did you mean...?" feature is really useful. But lately I've noticed that Google auto-corrects keywords from a query, without even asking. For example, if you search for [oper labs], all the top results include "opera labs", which is also highlighted in the title and the snippets.


From what I tried, Google is the only search engine that does that and, at least for this query, it does a pretty good job.