Bill Coughran from Google posted on Google's blog:

Last week we explained that we’re prioritizing our product efforts. As part of that process, we’ve decided to wind down Google Labs. While we’ve learned a huge amount by launching very early prototypes in Labs, we believe that greater focus is crucial if we’re to make the most of the extraordinary opportunities ahead.

In many cases, this will mean ending Labs experiments—in others we’ll incorporate Labs products and technologies into different product areas. And many of the Labs products that are Android apps today will continue to be available on Android Market. We’ll update you on our progress via the Google Labs website.

We’ll continue to push speed and innovation—the driving forces behind Google Labs—across all our products, as the early launch of the Google+ field trial last month showed.

Update 3:36pm: To clarify: we don't have any plans to change in-product experimentation channels like Gmail Labs or Maps Labs. We'll continue to experiment with new features in each of our products.