Josh Williams makes it official on the Gowalla blog today:
Gowalla, as a service, will be winding down at the end of January. We plan to provide an easy way to export your Passport data, your Stamp and Pin data (along with your legacy Item data), and your photos as well. Facebook is not acquiring Gowalla’s user data.
Gowalla in its original state was far superior to Foursquare. With recent updates it failed to be useful for me, but it is still sad to see it go.